- Russia has massed troops near Ukraine's border
- Russia also has troops in Belarus for drills
- Top US diplomat Blinken is in Berlin for talks
- President Biden warns Russia of response if it invades
- Kremlin says US threats risk destabilising situation
US Secretary of State Antony Blinken met European allies in Berlin on Thursday, seeking to present a united front ahead of last-ditch crisis talks with Russia aimed at preventing Moscow from attacking Ukraine.
The top US diplomat has been on a mission to head off war, which will culminate on Friday with a meeting with Russia's Foreign Minister Sergei Lavrov in Geneva. Blinken visited Kyiv on Wednesday and was meeting German, French and British ministers on Thursday in Berlin.
On Wednesday, US President Joe Biden gave his clearest indication yet that he believes an attack is likely: "My guess is he will move in," Biden said of Russian President Vladimir Putin. "He has to do something."
Western countries are trying to persuade Moscow not to launch a new assault against Ukraine, which it invaded in 2014. Russia has massed tens of thousands of troops on the border in recent months. It denies planning an attack but says it could take unspecified military action unless demands are met, including a promise from NATO never to admit Kyiv.
Biden and other Western leaders have threatened to impose economic sanctions on Russia if it again attacks Ukraine. Russia, already under sanctions since its last invasion, has largely brushed off the threat.
The Kremlin said on Thursday that US warnings of possible disastrous consequences for Russia would not help reduce tensions over Ukraine and could even destabilise the situation further.
Blinken vowed in Kyiv on Wednesday that Washington would pursue diplomacy as long as it could. In Berlin, he will give a speech intended to put into context the tensions in Europe and the stakes involved, a senior State Department official said.
Aimed at the European public as well as policymakers, the speech will try to cast the crisis over Ukraine as a critical moment for the rules-based international order, the official said.
US-Russia negotiations last week produced no breakthrough. Germany signalled on Tuesday that it could halt the Nord Stream 2 pipeline from Russia if Moscow invades Ukraine.
Blinken said on Wednesday the Russian build-up of troops was taking place with "no provocation, no reason".
Russia has also moved troops to Belarus for what it calls joint military exercises, giving it the option of attacking neighbouring Ukraine from the north, east and south.
Eight years ago it seized Crimea and backed separatist forces who took control of large parts of eastern Ukraine.
Russia denies planning a new invasion but says it feels menaced by Kyiv's growing ties with the West. It wants to prevent Ukraine ever joining NATO and for the alliance to pull back troops and weapons from eastern Europe.