DSG: The reason we meet is that we see negative signs, serious signs, risks of escalation, both on the ground and, I would say, verbally. There has to be a de-escalation, both physically and in terms of political language. There are some positive signs. There are calls for dialogue from all quarters. There are also intentions stated by authorities in Ukraine to have inclusive government with also representatives from eastern Ukraine, so we hope, as I said, that cool heads will prevail. That is what we all need to think of now. It is a very, very important responsibility, for all concerned, both inside and outside Ukraine.

Earlier on Saturday, Turkey's Foreign Minister Ahmet Davutoglu met with Ukraine's acting President Oleksandr Turchynov in Kiev. Afterward, he spoke at a joint news conference with lawmaker Mustafa Qirimoglu, the former chairman of the National Assembly of the Crimean Tatar People.

Mr. Davutoglu called on world powers to safeguard the rights of the region's Tatar minorities who he described as "kin." Tatars were persecuted during the Soviet era of Ukraine and Crimea.

"When it comes to the rights of our kin in Crimea, [Turkey] is in all sorts of efforts--a state of mobilization, so to say--for all sorts of initiatives," he added.

Latvia+Lithuania have invoked NATO art. 4 in response to #crimea NATO now obliged to hold emerg council meeting. Only 4th time in history
2:23 PM - 1 Mar 2014

22.21 We now have the White House read out of that call which lasted 90 minutes:

"President Obama spoke for 90 minutes this afternoon with President Putin of Russia about the situation in Ukraine. President Obama expressed his deep concern over Russia's clear violation of Ukrainian sovereignty and territorial integrity, which is a breach of international law, including Russia’s obligations under the UN Charter, and of its 1997 military basing agreement with Ukraine, and which is inconsistent with the 1994 Budapest Memorandum and the Helsinki Final Act. The United States condemns Russia’s military intervention into Ukrainian territory.

"The United States calls on Russia to de-escalate tensions by withdrawing its forces back to bases in Crimea and to refrain from any interference elsewhere in Ukraine. We have consistently said that we recognize Russia’s deep historic and cultural ties to Ukraine and the need to protect the rights of ethnic Russian and minority populations within Ukraine. The Ukrainian government has made clear its commitment to protect the rights of all Ukrainians and to abide by Ukraine’s international commitments, and we will continue to urge them to do so.

"President Obama told President Putin that, if Russia has concerns about the treatment of ethnic Russian and minority populations in Ukraine, the appropriate way to address them is peacefully through direct engagement with the government of Ukraine and through the dispatch of international observers under the auspices of the United Nations Security Council or the Organization for Security and Cooperation in Europe (OSCE). As a member of both organizations, Russia would be able to participate. President Obama urged an immediate effort to initiate a dialogue between Russia and the Ukrainian government, with international facilitation, as appropriate. The United States is prepared to participate.

Vladimir Putin had a telephone conversation with President of the United States Barack Obama on the American side’s initiative.

The two presidents discussed in detail various aspects of the extraordinary situation in Ukraine.

In reply to Mr Obama’s concern over the possibility of the use of Russian armed forces on the territory of Ukraine, Vladimir Putin drew his attention to the provocative and criminal actions on the part of ultranationalists who are in fact being supported by the current authorities in Kiev.

The Russian President spoke of a real threat to the lives and health of Russian citizens and the many compatriots who are currently on Ukrainian territory. Vladimir Putin stressed that in case of any further spread of violence to Eastern Ukraine and Crimea, Russia retains the right to protect its interests and the Russian-speaking population of those areas.