Russia on Tuesday warned Saudi Arabia against supplying Syrian rebels with shoulder-launched missile launchers, saying such a move would endanger security across the Middle East and beyond.

The Russian foreign ministry said in a statement that it was "deeply concerned" by news reports that Saudi Arabia was planning to buy Pakistani-made shoulder-launched surface-to-air missiles and anti-tank systems for armed Syrian rebels based in Jordan.

Moscow pledged Tuesday it would not intervene in the crisis in neighboring Ukraine but said the country should not be forced to choose between Russia and the West.

"We confirmed our principled position of non-intervention in Ukraine's internal affairs and expect that everyone follows similar logic," Foreign Minister Sergei Lavrov said.

More than 400 Russian protesters faced court hearings on Tuesday a day after police detained them at a central Moscow rally, the largest such wave of arrests in nearly two years.

The demonstrators had gathered near Red Square late on Monday in support of activists jailed earlier in the day for staging "mass riots" in May 2012, a key case seen as a symbol of the harsh crackdown on dissent under President Vladimir Putin's latest term.

Francois Hollande told Russia's Vladimir Putin on Monday Ukraine must have a "peaceful transition", saying it was vital to ensure the country remained unified, the French president's office said.

Hollande also said the formation of a new government in Ukraine must lead to a presidential election and vital reforms, in a telephone conversation with the Russian president.

French Foreign Minister Laurent Fabius on Monday urged Russia to continue to offer financial assistance to Ukraine, telling reporters in Beijing "there is no time to lose" for the crisis-hit country.

"What we know is that Ukraine's financial situation is very bad, that's for certain," Fabius said, as the global community discussed support for Ukraine, which has appealed for $35 billion in western aid.

The Russian Foreign Ministry on Monday strongly criticized the new Ukrainian leadership, saying it used dictatorial methods and discriminated against ethnic Russians.

"They have set a course to suppress those who do not agree in various regions of Ukraine using dictatorial and sometimes even terrorist methods," the ministry said in a statement. Moscow also slammed new legislation that it said aimed to "restrict the humanitarian rights of Russians".

Russia's economy minister warned Ukraine in an interview on Monday that Moscow will raise import duties on its goods if Kiev signs a partnership agreement with the European Union.

"We say to Ukraine: you have the right to go your own way," Alexei Ulyukayev was quoted as telling German business daily Handelsblatt.

Russia is calling its ambassador to Ukraine back to Moscow for "consultations", the foreign ministry said Sunday, after tumult in Kiev led to pro-Russian leader Viktor Yanukovych being toppled and replaced with a pro-EU leadership from the opposition.

"Due to the escalation of the situation in Ukraine and the necessity of analyzing the existing situation from all sides, a decision has been made to recall the Russian Ambassador to Ukraine (Mikhail) Zurabov to Moscow for consultations," the foreign ministry said in a statement late Sunday.

Ukraine's new interim president said on Sunday that he was open to dialogue with Russia as long as Moscow respected his country's decision to seek closer ties with the European Union.

"We are ready for a dialogue with Russia... that takes into account Ukraine's European choice, which I hope will be confirmed in (presidential) elections" set for May 25, Oleksandr Turchynov said in a television address.

German Chancellor Angela Merkel and Russian President Vladimir Putin agreed Sunday that Ukraine's "territorial integrity" must be ensured, the German government spokesman said, as the U.S. said it was in no one's interest to see Ukraine break apart.

Merkel spoke by phone with Putin and "both agreed that Ukraine must quickly get a government capable of acting and its territorial integrity must be preserved," Steffen Seibert said.