ISTANBUL — Fighting erupted Tuesday between Armenia and Azerbaijan, the latest flare-up in their decades-long confrontation in the South Caucasus, killing as many as 100 service members and raising the prospect of fallout from the war in Ukraine spreading instability across a wider region.
Each side blamed the other for the fighting that broke out along their border early on Tuesday, the worst escalation of hostilities between the two countries since a 2020 war and a cease-fire brokered by Russia that ended large-scale fighting.
The resurgence of conflict on Russia’s southern rim — and between two former Soviet republics — raised concerns about what President Vladimir V. Putin of Russia, already smarting from humiliating defeats in recent days in northeastern Ukraine, might do.
By 9 a.m. local time Tuesday, Russia had announced that it had brokered another cease-fire. But later in the day, the American secretary of state, Antony J. Blinken, said he was concerned that Moscow might try to “stir the pot” in the conflict to create a distraction from Ukraine.
The flare-up also poses a problem for the European Union, which over the summer turned to officials in Baku, the Azerbaijani capital, in its frenzied search for additional natural gas supplies to make up for the loss of Russian imports. The bloc has been working hard to secure a peace deal between the warring countries.
Although tensions had been bubbling between Azerbaijan and Armenia for months, with localized shelling and gunfire causing casualties in the single digits, Tuesday’s clashes surprised many for their ferocity. There were concerns that the violence would set back the efforts to get the countries to sign a peace accord.
On Tuesday, for the first time in 30 years of a largely frozen conflict over the disputed territory of Nagorno-Karabakh and surrounding districts, Azerbaijan attacked Armenian air defense and artillery systems based inside Armenia. Analysts shared satellite mapping by NASA’s Fire Information for Resource Management Systems that showed heavy fire in multiple locations inside Armenia.
Prime Minister Nikol Pashinyan of Armenia said that 49 Armenian service members had died overnight in artillery and mortar strikes by the Azerbaijani Army.
Azerbaijan’s defense ministry accused Armenia of a number of “large-scale provocations” and said it had been forced to retaliate. The ministry later announced that 50 Azerbaijani service members — 42 soldiers and eight border guards — had been killed.
Mr. Pashinyan, speaking before Armenia’s Parliament, denied that his country had provoked Azerbaijan, and accused it of attacking Armenian territory first. He said that the intensity of hostilities had decreased later in the day, but that attacks from Azerbaijan were continuing on one or two fronts.
Washington urged both sides to cease hostilities.
“Whether Russia tries in some fashion to stir the pot, to create a distraction from Ukraine, is something we’re always concerned about,” Mr. Blinken told reporters at an event in Indiana, Reuters reported. The secretary of state said Russia could also use its influence in the region to help “calm the waters.”
Clashes in the Caucasus, a tempestuous but often ignored region, pose challenges for both Moscow and the West, analysts warn.
Russia’s preoccupation with the war and its perceived weakness have helped destabilize the situation in the Caucasus, Thomas de Waal, a senior fellow at Carnegie Europe, said recently in an article in Foreign Affairs.
“Its setbacks in Ukraine have limited Russia’s capacity to project power in its neighborhood,” he wrote. “Its military and diplomatic chiefs are distracted, and local powers can more easily ignore its instructions and threats.”
Russia and Armenia are part of a Moscow-led military alliance whose charter stipulates that an attack against one member would be treated as an attack against all. Russia has maintained military bases in Armenia for decades and has had up to 2,000 troops deployed as peacekeepers in the disputed region since 2020.
Yet Azerbaijan was in a relative position of strength, militarily and politically, after its successes in the war of 2020, Mr. de Waal said. He cited Baku’s signing of a nonaggression pact with Russia, its success getting diplomatic support from Turkey, and its role supplying the European Union with gas as Russian gas comes under pressure from sanctions.
“Azerbaijanis, they still have unfinished business with the Armenians,” he said. “And right now they feel that they are in a superior position to use both diplomacy and force to get those things.”
The outbreak of clashes in the Caucasus is an added test for Russia, Mr. de Waal said in an interview Tuesday.
“When Russia is flat on its back because of a new Ukraine offensive,” he said, “do they want to commit themselves to defending Armenia and alienating Azerbaijan?”
Baku has increased leverage with Russia as Moscow seeks alternative energy and trade transit routes with Iran and Asia, as well as with Europe, Laurence Broers, associate fellow at the Russia and Eurasia program at Chatham House in London, wrote on Twitter. He predicted that clashes between Azerbaijan and Armenia would continue.
“Even if outside powers, most likely Moscow, broker a cease-fire, such escalations will likely continue as part of a coercive bargaining dynamic, and per latest reports, over a wider area,” he wrote.
Farid Shafiyev, a former diplomat and director of the government-funded Center for Analysis of International Relations in Baku, said, “The real reason for these occasional clashes is because no real peace treaty exists.”
The energy crisis precipitated by the war in Ukraine raises the stakes of a new war in the Caucasus enormously.
Gazprom, Russia’s state natural gas company, has nearly turned off the gas taps to punish the European Union for its support of Ukraine, leaving the bloc scrambling to make up for the lost fuel, and households and businesses facing price increases that will most likely push European economies into recession next year.
In mid-July, the European Commission president, Ursula von der Leyen, visited Azerbaijan to sign an agreement with President Ilham Aliyev. The bloc plans to increase its imports of gas from the country from 8 billion cubic meters a year to 12 billion next year, and to 20 billion by 2027.
To make this happen, Ms. von der Leyen and Mr. Aliyev agreed, the E.U. will back a broad expansion of the Southern Gas Corridor to carry the gas to several E.U. members and connect it further to the continent’s grid, covering Greece, Bulgaria and Italy, among other countries. Ms. von der Leyen also announced dozens of millions of euros worth of investments.
“Thank you for stepping up and for supporting the European Union,” she said, calling Azerbaijan a “reliable, trustworthy” partner.
There was no mention of the conflict in Ms. von der Leyen’s speech. In his own, Mr. Aliyev referred to Karabakh as “liberated” and said the region held potential to contribute to renewable energy generation.
Experts quickly argued that Azerbaijan did not have the capacity to reach the targets set by the bilateral agreement and said the deal left the E.U. on the ropes.
Ms. von der Leyen was also chastised for making only the gentlest of comments about Azerbaijan’s much-condemned human-rights record and reserving them for her closing sentences, much to the chagrin of civil society organizations.
“To reach Azerbaijan’s full potential, it is important to create the right conditions for investor confidence,” Ms. von der Leyen said. “This includes a greater involvement of civil society, and a free and independent media.”
Daniel Freund, a European Parliamentarian, denounced the gas deal when it was announced. “Dictatorships are not ‘trustworthy,’” he said. “Not for democracies, not for Europe and especially not for the citizens they brutally oppress.”
For some observers, the agreement amounted to a desperate move that compromised the bloc’s interests in the region by overly strengthening Baku’s hand.
Charles Michel, the president of another key E.U. institution, the European Council, has been personally engaged in the peace talks in the region. Now they appear to be in tatters, but Mr. Michel is still trying. On Tuesday, he said he was in contact with both the Azerbaijani and Armenian leaders. He called for a “complete and sustainable cease-fire.”
Carlotta Gall reported from Istanbul, and Matina Stevis-Gridneff from Brussels. Ivan Nechepurenko contributed reporting from Tbilisi, Georgia; Cora Engelbrecht from London; and Safak Timur from Istanbul.
