France and Germany Saturday threatened Russia with "consequences" if Moscow disrupts Ukrainian presidential elections later this month, stepping up diplomatic pressure on the eve of "illegal" referendums the West fears will split the country apart.

In a joint statement, French President Francois Hollande and German Chancellor Angela Merkel also urged Ukraine's security forces to stop their offensive on rebel-held positions in the run-up to the planned May 25 presidential part.

Germany's Angela Merkel welcomed French President Francois Hollande to a picturesque Baltic coastal town Friday for talks meant to strengthen the personal chemistry between the two leaders at the heart of Europe.

Braving a slight drizzle, Merkel greeted Hollande in the seaside resort of Sassnitz, saying that getting to know each others' homes, "in view of the many problems we have to discuss, is a good thing."

Paris prosecutors have launched a judicial investigation for involuntary homicide following the Malaysia Airlines plane crash, a judicial source said Friday.

The probe was launched on Wednesday. Four French nationals were among the passengers, including three students from the French school in Beijing, and the mother of two of the pupils.

French Eurovision hopefuls Twin Twin on Friday said their country could fare better in the contest if their entries were a bit more fun and colorful.

The group, set to compete in Saturday's final with electro-pop party anthem "Moustache", said France's dismal record in the contest over the past three decades was due to "a mix of things."

Germany's Angela Merkel from Friday will host French President Francois Hollande in a picturesque Baltic coastal town for informal talks meant to strengthen the personal chemistry between the two European leaders.

A range of pressing issues -- including the tense standoff with Moscow over Ukraine, European elections in two weeks and a possible major trans-border corporate deal -- will be on the agenda of the two-day visit starting 1400 GMT on what is the EU's official "Europe Day".

Several European countries met Thursday with officials from the United States, Turkey, Morocco, Jordan and Tunisia to discuss how to stop young Islamist fighters joining rebels in Syria.

The fear is that the young fighters become even more radicalized and return home with extensive military experience which can be put to terrorist ends, Belgian Interior Minister Joelle Milquet said.

U.S. officials on Thursday voiced concern at the sale of French warships to Moscow as they mull tougher sanctions on Russia for the political upheaval triggered by the crisis in Ukraine.

"We have regularly and consistently expressed our concerns about this sale even before we had the latest Russian actions and we will continue to do so," Assistant Secretary for Europe Victoria Nuland told U.S. lawmakers ahead of a visit next week to Washington by French Foreign Minister Laurent Fabius.

U.S. President Barack Obama has no plans to meet one-on-one with his Russian counterpart Vladimir Putin in June when both attend the D-Day anniversary in France, the White House said Thursday.

Russia's intervention in the political crisis in Ukraine has triggered the worst chill in relations between Washington and the Moscow since the end of the Cold War.

Russian President Vladimir Putin will attend ceremonies in France next month marking the 70th anniversary of D-Day despite the Ukraine crisis, the ambassador to Paris said Thursday.

"President Putin has been invited by President (Francois) Hollande to take part in the ceremonies to commemorate the Normandy landings on June 6. He has accepted the invitation. He will be coming on June 6," Alexander Orlov told BFM television.

France said Thursday it will deploy 3,000 soldiers to combat Islamist violence in the vast and largely lawless Sahel region of Africa.

"Our role is to pursue counter-terrorism in north Mali, the north of Niger and in Chad," Defense Minister Jean-Yves Le Drian said in a television interview.