By Naftali Bendavid and Anton Troianovski

European governments, jolted by the downing of a passenger plane over eastern Ukraine that killed nearly 300 people, are contemplating a major expansion of sanctions on Russia as early as next week.

European Union leaders decided in recent days to expand the penalties to a broad new category of people and companies. But the apparent shooting down of a plane carrying more than 200 EU citizens has intensified a desire to act quickly and forcefully, including sanctions against oligarchs with ties to the Kremlin.

In Brussels, some diplomats described the incident as a game-changer. "It would have major consequences if it was certain it came from the rebels-- major consequences," said one official. President Barack Obama, at the White House, called the tragedy "a wake-up call for Europe."

How far the bloc will go, however, will depend in whether the 28 countries can agree on a position.

The EU, whose sanctions have generally fallen short of the tougher measures imposed by the U.S., has been hampered in part by a disagreement among members. Some southern European nations, led by Italy, and others including Hungary and Bulgaria that depend on Russian energy, have resisted harsher sanctions.

One official said the potential for retaliatory actions by Russia "are weighing quite heavily on member states."

Some of that caution was evident Friday. A spokesman for the Italian foreign ministry said only that Italy "supports EU unity" on crafting a response.

The French foreign ministry declined to discuss whether Paris would push for tougher sanctions when EU foreign ministers meet in Brussels next week. Paris opposes any measures that would hinder its plans to deliver the first of two Mistral-class carriers--capable of launching amphibious attacks and helicopters--to Russia in October.

But Gérard Araud, France's ambassador to the United Nations, tweeted, "Russia shouldn't be surprised the thugs it arms are acting like... thugs."

Perhaps most important is the response of Germany, and officials in Berlin said the disaster could augur a turning point in the crisis.

EU leaders agreed last week to expand sanctions to those who have supported Moscow's decision makers. But that gives the bloc wide latitude, and the crash could prompt the EU to penalize a larger number of people and organizations than they otherwise would have.

"This is a platform that gives us a lot of leeway to act on a new level, " German Chancellor Angela Merkel said in a news conference.

Sanctions against entire sectors of the Russian economy still don't appear imminent. But adding large Russian companies to the EU sanctions list could prove as damaging as targeting specific sectors, German officials said.

The large number of victims from the Netherlands, a core EU country and one that has so far been relatively cautious about sanctions, could also help change dynamics inside the 28-member bloc.

EU officials said that while they need clear evidence of the culprits before acting, that may not mean waiting until a comprehensive investigation is complete. When the foreign ministers gather Tuesday, they are expected to discuss new names that will be added to the sanctions list, probably by week's end.

"The first test is, can international investigators get access?" said one EU official. "Will the bodies be returned to loved ones? Will the black box be provided?"

Some diplomats suggested the tragedy could even provide a political opening for the sides to move closer. Western leaders had been trying to arrange a conference call with the separatists for some time, for example, but the call only came together Thursday after the crash, a senior EU official said.

In the call, members of the "Trilateral Contact Group"--which includes the Organization for Security and Cooperation in Europe, as well as Ukraine and Russia--spoke by video with separatist groups in Donetsk. The separatists agreed to secure the crash site and provide access to international investigators, the OSCE said.

In Germany, arguably Europe's most influential country, extensive media coverage of the disaster, and the widespread suspicion that the separatists are responsible, could influence the debate. Polls have shown that most Germans oppose sanctions against Russia.

But Manfred Güllner, one of Germany's top pollsters, cautioned that many Germans might continue to oppose sanctions because they believe the Kiev government, the EU and the U.S. are as culpable as Russia for stirring up tensions.

The disaster may also influence the sanctions debate within the German government, which has been divided. Some key advisers to Ms. Merkel have been pushing for harder sanctions while the Foreign Ministry has sought to proceed more cautiously, people familiar with the matter say.

"If in the course of the investigations it should become clear that one of the parties in the conflict has the lives of hundreds of completely innocent victims on its conscience," said foreign minister Frank-Walter Steinmeier, "this would be a crime outside of all imagination."

Matthew Dalton in Brussels, Stacy Meichtry in Paris, Laurence Norman in Vienna, Deborah Ball in Rome contributed to this article.

Write to Naftali Bendavid at naftali.bendavid@wsj.com and Anton Troianovski at anton.troianovski@wsj.com

(END) Dow Jones Newswires

July 18,2014 14:07 ET (18:07 GMT)

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