NATO wants a constructive relationship with Russia but for that to happen it must engage Moscow from a position of strength, alliance head Jens Stoltenberg said Tuesday.

The US-led military pact had helped ensure stability in Europe, he said, but now, with its intervention in Ukraine, Russia was "trying to roll back the progress we have made".

Russian police have raided the home of opposition activist Maria Gaidar, daughter of a former prime minister under Boris Yeltsin, as part of a probe against another top Kremlin critic, a spokeswoman said Tuesday.

"A search went on for several hours led by investigators and police officers on Monday," said spokeswoman Nataliya Malysheva of the Maria Gaidar Foundation.

Russia announced Tuesday it will recognize separatist polls in Ukraine next weekend, fueling tensions with the country's newly elected pro-Western leaders as they negotiate on forming a coalition government.

The rebel elections on Sunday should "go ahead as agreed," Russian Foreign Minister Sergei Lavrov said.

French President Francois Hollande held talks with the leaders of Armenia and Azerbaijan Monday in a fresh push to end the festering conflict over the disputed region of Nagorny Karabakh.

The summit in Paris enabled "the resumption of a direct dialogue" between the presidents of the two countries, though no accord was reached, the French presidency said in a statement after the talks ended.

Ukraine's snap parliamentary election was mostly fair, the leading group of Western observers said Monday.

"At this crucial moment for the future of their country, Ukraine’s institutions and voters responded to daunting challenges with an election that largely upheld democratic commitments," said Kent Harstedt, head of the OSCE observer mission.

Parties backing a peace process to end the conflict with pro-Russian rebels in east Ukraine won a clear victory at Sunday's parliamentary polls, Russia's deputy foreign minister said Monday.

"It is already clear that parties which support a peaceful resolution of the internal Ukrainian crisis received a majority," Grigory Karasin was quoted as saying by state-run Ria Novosti news agency. 

Ukraine's pro-Western and moderately nationalist parties were on course Monday to score a crushing election win that boosted President Petro Poroshenko's bid to lead his country closer to Europe and end a pro-Russian revolt.

A partial vote count and exit polls showed overwhelming support for Poroshenko's drive to break the ex-Soviet republic of 45 million from Russia's orbit, while attempting to defuse a war with separatist insurgents that has killed at least 3,700 people.

French President Francois Hollande hosts leaders from Armenia and Azerbaijan Monday as Europe makes a fresh push to end the festering conflict over Nagorny Karabakh.

Germany's Foreign Minister Frank-Walter Steinmeier visited both countries last week after a sharp escalation in violence over the disputed region in recent months as war raged in Ukraine.

Pro-Western and nationalist parties scored a crushing victory on Sunday in Ukraine's snap parliamentary polls, which were boycotted by pro-Russian rebels in the separatist east, exit polls showed.

The Ukrainian president's Petro Poroshenko Bloc and the People's Front group of Prime Minister Arseniy Yatsenyuk won 23 and 21 percent of the vote respectively, while the Opposition Party linked to ousted Russian-backed president Viktor Yanukovych won nearly eight percent, two respected surveys said.

U.S. Secretary of State John Kerry has urged Moscow to fully implement last month's ceasefire agreement on Ukraine, the State Department said in a statement Saturday.

The peace deal reached last month in the Belarussian capital Minsk between Kiev, Moscow and the pro-Russian separatists in east Ukraine includes monitoring and verification by the Organization for Security and Co-operation in Europe (OSCE) on both sides of the border.