The Kiev authorities should block the presidential bid of the leader of Pravy Sektor, or Right Sector, movement, Dmytro Yarosh, the Russian foreign ministry's rights envoy said Sunday.

"The de facto authorities in Kiev and their Western protectors must close the road to power for the neo-fascist Yarosh and his supporters," foreign ministry rights envoy Konstantin Dolgov wrote on Twitter.

Standing in the shadow of a massive, grey former KGB building in a busy Vilnius street, Lithuanian pensioner Rimantas Gucas worries history could repeat itself if the West fails to stop Russia from absorbing Ukraine's Crimean peninsula.

As Lithuania marks 24 years since it broke free from the crumbling Soviet Union and a decade since it joined NATO, people here and in fellow Baltic states Estonia and Latvia are jittery over Russian moves in Crimea.

Sarah Palin offered unsolicited advice Saturday to President Barack Obama on containing Russian aggression, saying "the only thing that stops a bad guy with a nuke is a good guy with a nuke."

The Republican former vice presidential candidate used a predominantly crass tone throughout her appearance at the Conservative Political Action Conference.

Victims of Stalin's mass deportations in 1944, Crimea's Tatar Muslim minority look wearily on next week's referendum on joining Russia, which could well bring the crisis on the tense peninsula to new heights.

At the Great Mosque in Bakhchysaray, near the southern tip of the Black Sea region, the local Tatar representative Akhtem Chiygoz slams the March 16 vote as "illegal".

Ukraine's former Prime Minister, Yulia Tymoshenko, has arrived in Berlin for medical treatment, a hospital official said Saturday.

The face of the pro-Western Orange Revolution in 2004, who suffers from herniated discs, started medical examinations on Saturday morning, said Karl-Max Einhaupl, director of the Charite University Hospital, Berlin.

President Barack Obama and key European allies expressed "grave concern" Saturday over Russia's actions in Ukraine as Washington warned further military escalation could jeopardize chances of brokering a diplomatic solution to the crisis.

The White House said Obama discussed Ukraine in calls with French counterpart Francois Hollande, British Prime Minister David Cameron and Italian leader Matteo Renzi.

Russia is considering halting foreign inspections of its strategic weapons arsenal, including nuclear-capable missiles, in response to "threats" from the West over the Ukraine crisis, the defense ministry said Saturday.

"The unfounded threats towards Russia from the United States and NATO over its policy on Ukraine are seen by us as an unfriendly gesture that allows the declaration of force majeure circumstances," a high-ranking defense ministry official, who was not named, said in a statement to all Russian news agencies.

As world powers and international institutions cobble together aid packages for a debt-laden Ukraine on the brink of default, regular Ukrainians feeling the pinch fear they will see none of the cash.

At an outdoor market north of Kiev's city center on Friday, stallholders sold everything from colorful stuffed toys to freshly baked pastries and bouquets of flowers for International Women's Day.

Russia is open to having an "honest, equal" dialogue with foreign states on the crisis in Ukraine, Foreign Minister Sergei Lavrov said Saturday.

"We are open to an honest, equal and objective dialogue with our foreign partners to find a way to help all of Ukraine come out of the crisis," Lavrov said at a televised news conference in Moscow with his Tajik counterpart, in a clear reference to the West.

Russian President Vladimir Putin has seemingly been in the "deep freeze" since the Cold War and is applying its outdated KGB mentality in Ukraine, Britain's deputy prime minister said Saturday.

Speaking to The Guardian newspaper, Nick Clegg said Putin was applying "yesterday's divisions and arguments to today's problems".