Obama: G-7 prepared to impose additional costs on Russia if needed

President Obama: G-7 nations united in support for Ukraine

President Barack Obama on Thursday encouraged Russia to open talks with the new government coming into power in Ukraine or face continuing costs imposed by the world's leading economies if its provocations continue.

Obama emerged from two days of meetings with the Group of Seven saying it was a chance for the gathered leaders to make sure they are in "lockstep" on a strategy going forward in uncertain times in Ukraine. He urged Russian President Vladimir Putin to "enter into a dialogue" with President-elect Petro Poroshenko, who is being inaugurated Saturday after winning the May 25 election.

"Russia needs to seize that opportunity," Obama said. "Russia needs to recognize that President-elect Poroshenko is the legitimately elected leader of Ukraine and engage the government in Kiev."

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Obama spoke at a news conference with British Prime Minister David Cameron in Brussels after the two met privately following the closing of a gathering of the Group of Seven nations. Cameron said Russia's actions in Ukraine are at odds with the leaders' democratic values. "From the outset of this crisis, the G-7 have stood united."

The G-7 meeting was originally supposed to take place in Sochi, Russia, and include Putin, but the leaders froze him out and moved the site to Brussels after Russia annexed the Crimean Peninsula. After an opening dinner Wednesday night, the group said in a joint statement that they condemn Russia's ongoing violation of Ukraine's sovereignty and its annexation of Crimea.

President Obama: Putin should seize this moment

Obama was heading to Paris Thursday evening for dinner with French President Francois Hollande. Ukraine also topped their agenda.

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The U.S. and Europe started out showing solidarity against Putin by levying sanctions against the Russian president. But diverging approaches are emerging now that European leaders are planning separate, private meetings with Putin in Paris while Obama is steering clear of him.

Hollande said Thursday that it's up to Obama whether he wants to meet with Putin and noted that both men would be at events commemorating the 70th anniversary of the Allied invasion of Normandy Friday, along with other leaders.

"The important thing is we have the same language, the same arguments on Ukraine all together," Hollande said in a brief exchange with reporters traveling with Obama. "We are seven."

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—By The Associated Press