The US has ordered the relatives of its embassy staff in Ukraine to leave amid rising tension in the region.
US Secretary of State Antony Blinken met with staff at the US embassy in the Ukrainian capital Kyiv (or Kiev) on 19 January. Photo: AFP
The State Department has also given permission for non-essential staff to leave and urged US citizens in Ukraine to consider departing.
In a statement, it said US citizens should not travel to Russia due "to ongoing tension along the border with Ukraine", further warning on the conflict with Kyiv as Moscow amasses troops near its neighbour.
The State Department said there were reports that Russia is planning significant military action against Ukraine.
Russia has denied claims that it is planning to invade Ukraine.
"There are reports Russia is planning significant military action against Ukraine," the advisory from the State Department said.
It added that the security conditions are "unpredictable and can deteriorate with little notice".
The State Department reissued its travel advisory that says Americans should not travel to Russia, adding: "US citizens are strongly advised against travelling by land from Russia to Ukraine through this region."
The head of the military defence alliance NATO has warned there is a risk of fresh conflict in Europe after an estimated 100,000 Russian troops amassed on the border.
On Saturday, some 90 tonnes of US "lethal aid" including ammunition for "front-line defenders" arrived in Ukraine.
US Secretary of State Anthony Blinken said the government were putting together a "series of actions that would figure into President Putin's calculus" including beefing up defences in Ukraine with more military assistance.
Russia has seized Ukrainian territory before, when it annexed Crimea in 2014, after the country overthrew their pro-Moscow president.
Ever since, Ukraine's military has been locked in a war with Russian-backed rebels in areas of the east near Russia's borders. An estimated 14,000 people have been killed in the Donbas region.
Meanwhile, the UK embassy in Ukraine said some staff and dependants are being withdrawn from Kyiv in response to the growing threat from Russia.
On Sunday, the UK foreign office accused Putin of planning to install a pro-Moscow figure to lead Ukraine's government.
UK ministers have warned that the Russian government will face serious consequences if there is an incursion.
- BBC / Reuters