President Barack Obama on Saturday asked President Vladimir Putin to pull his forces out of Crimea, Ukraine saying their presence violated international law.
But pressure is mounting on Obama to do more, with lawmakers wanting him to spell the 'costs' he had warned Russia of earlier. Others demanded targeting economic sanctions.
In a phone call lasting 90 minutes, Obama expressed his 'deep concern Russia’s clear violation of Ukrainian sovereignty and territorial integrity, which is a breach of international law', according to a readout of the call issued by the White House.
Read: Russian president Putin gets parliament nod, set to invade Ukraine; troops seize Crimea
And, he told the Russian president the US was suspending its participation in the upcoming G-8 meeting in Sochi, venue of the recently concluded winter Olympics.
But Putin pushed back, telling Obama of the 'provocative and criminal actions on the part of ultra-nationalists who are in fact being supported by the current authorities in Kiev'.
A woman holds a sign during a demonstration in front of the Russian Embassy in Kiev. (AFP photo)
According to details of the conversation issued by Putin’s office, he told Obama 'Russia retains the right to protect its interests and the Russian-speaking population of those areas'.
The US has urged Russia to directly engage Ukrainian authorities on these concerns and seek monitors under the auspices of the UN security council and the Organization for Security and Cooperation in Europe.
Read: Ukraine puts forces on combat alert, warns of war
The US was talking to its western allies on the way forward. 'I convened a call this afternoon with my counterparts from around the world, to coordinate on next steps,' said secretary of state John Kerry in a statement, adding, 'We were unified in our assessment and will work closely together to support Ukraine and its people at this historic hour.'
But pressure is mounting on Obama at home to do more. 'Every moment that the United States and our allies fail to respond sends the signal to President Putin that he can be even more ambitious and aggressive in his military intervention in Ukraine,' said senior Republican senator John McCain.
He asked the president to spell out the 'costs' of military intervention that he had warned Russia of on Friday, the day before Putin sought, and got, his parliament’s permission to send troops into Ukraine.
Another Republican senator, Bob Corker, asked the president to lead international efforts to stop Russian military intervention in Ukraine, including 'targeted economic sanctions'.
Even less hawkish Americans were demanding more. Strobe Talbott, former deputy secretary of state in the Clinton Administration, said in a tweet, '‘Sticks & stones will break my bones, but words will never hurt me.’ There's a Russian version of that ditty, & Putin's humming it now.'
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