By Andrew Higgins
June17, 2015

The European Union is set to extend by six months economic sanctions against Russia, calming fears that Greece’s acrimonious negotiations over its debt crisis might allow Russia to break the unity of the 28-nation bloc in its response to the conflict in Ukraine.

A decision to prolong the sanctions, which expire at the end of July, was made by European ambassadors in Brussels on Wednesday and is expected to be ratified at a meeting of foreign ministers early next week in Luxembourg, diplomats in Brussels said.

Moscow lobbied hard against a renewal of the sanctions, imposed last year in tandem with similar measures by the United States after Russia annexed Crimea in March and then provided support to separatist rebels in eastern Ukraine. Decisions on sanctions require unanimity, so Russia needed to win over only one European Union country to block an extension. But it failed in efforts to secure a blocking vote from any of the countries that have shown little enthusiasm for sanctions. These include Greece, Cyprus and Hungary, all of which Moscow has actively courted.

Jacek Saryusz-Wolski, a Polish member of the European Parliament and vice chairman for foreign affairs of the assembly’s largest political grouping, said he had worried that Greece’s left-wing prime minister, Alexis Tsipras, might use his country’s veto power to try to secure bailout money from Russia if deadlocked talks with Western creditors yielded no new funds.

“My fear was that he intended to auction his veto in both Brussels and Moscow,” Mr. Saryusz-Wolski said. In the end, he added, “Moscow was not able to put a sufficiently big envelope on the table.”

Mr. Tsipras, who visited Moscow in April for talks with President Vladimir V. Putin, is scheduled to make another trip to Russia on Thursday, as finance ministers from the 19 countries that use the euro meet in Luxembourg to discuss Greece’s debt crisis. Unless Greece gets money from somewhere in the next two weeks, it is expected to default on loans from the International Monetary Fund.

Mr. Saryusz-Wolski cautioned that the decision to extend sanctions was preliminary and could still be reversed or delayed when European Union foreign ministers meet next week. Diplomats in Brussels, however, said they were confident the agreement struck by ambassadors on Wednesday would hold.

For months, a billionaire-funded Ukrainian militia and whip-wielding Cossacks have been locked in a war of waiting near the long-contested Donetsk airport.

The United States lobbied against any letup in sanctions, securing agreement from the German chancellor, Angela Merkel, and other leaders at a Group of 7 summit meeting last week that they should remain in place until Russia helps to fully put in place a shaky peace plan for eastern Ukraine agreed in Minsk, Belarus, in February.

The Minsk deal committed both pro-Russian rebels and Ukrainian government forces to a cease-fire and the withdrawal of heavy weapons. Fighting has continued nonetheless, with recent weeks seeing a particularly serious flare-up in hostilities.

“If the European Union had not managed to maintain sanctions after all this, it would have seriously damaged its credibility,” said Amanda Paul of the European Policy Center, a Brussels research institute. She predicted that Russia would keep up pressure in eastern Ukraine and on the European Union by trying to woo countries like Greece into blocking sanctions in the future.

While working to reverse Western sanctions amid a slump in its economic growth, Russia has all along insisted that the measures would have little impact on an economy also hit by a fall in world oil and gas prices, and that they would not sway Kremlin policy. On Wednesday, Russia’s finance minister, Anton Siluanov, was quoted by Russian news media as saying that Moscow had already taken an extension of the measures into account in its economic planning, Reuters reported.

Some European nations, notably the Baltic States and Poland, pushed for tougher sanctions against Russia but settled for a simple extension of existing restrictions on access to capital by Russian banks and selected companies involved in energy and defense.