Ukraine's Zelensky visits frontline amid Russian invasion fears

Ukraine's President Volodymyr Zelensky visited the country's eastern frontline on Monday, as fears in Kiev mount that Russia is preparing to invade its south-western neighbour.

Ex-Soviet Ukraine has been fighting pro-Russia separatists in its eastern Lugansk and Donetsk regions since 2014, shortly after Moscow seized Crimea.

Kiev and its Western allies accuse the Kremlin of supporting the separatists -- claims Moscow denies -- in a conflict that has claimed over 13,000 lives.

"I am honoured to be with you today," Zelensky told Ukrainian troops while visiting their positions in the Donetsk region.

"Thank you for protecting the sovereignty and territorial integrity of Ukraine," he said, according to a statement released by his office.

"I am convinced that with people like you, we will definitely win."

Images released by the presidency showed the 43-year-old leader in the trenches clad in a helmet and bulletproof vest handing out awards to Ukrainian soldiers and shaking their hands.

Ukraine's armed forces, which were formed after Kiev gained independence from its Soviet-era master Moscow in 1991, were celebrating their 30th anniversary on Monday.

Zelensky's visit came on the eve of talks between Russian President Vladimir Putin and his US counterpart Joe Biden, who is expected to underscore Washington's concerns over Russian military activities near Ukraine.

The United States and Kiev's Western allies have for weeks accused Russia of massing troops near Ukraine and planning an invasion.

Russia has dismissed the allegations as hysteria whipped up to stoke tensions.