Ukraine has banned Russian men aged between 16 and 60 from entering the country, amid fears Moscow is planning an invasion.

Ukrainian president Petro Poroshenko said the restrictions have been imposed to prevent Russians from forming "private armies" in his country.

Moscow has been supporting Russian separatists in the east of the country with troops and weapons.

Petro Poroshenko warns there is 'no red line for Putin'

Mr Poroshenko also told Sky News he has evidence that Russian tanks are massing along his country's border.

Ukraine imposed martial law earlier this week following an escalation in the long-simmering conflict between the two nations over Crimea, which Moscow seized in 2014.


In a violent confrontation, Russian border guards fired on and captured three Ukrainian ships in the Black Sea.

The Ukrainian vessels had been trying to pass through the Kerch Strait on their way to the Sea of Azov.

The latest crisis led US President Donald Trump to cancel a meeting with Russia's Vladimir Putin at a summit of world leaders in Argentina.

Mr Trump said it would not be appropriate as Moscow had still not released the 24 crew members of the seized vessels.

A Crimea court has ruled that the sailors will be detained for two months pending the outcome of an investigation.

Meanwhile, Ukrainian intelligence officers have been searching the home of the the head of Kiev's largest and oldest monastery, which is part of the Russian Orthodox Church.

Spy chief Ihor Guskov said the Russian cleric Father Pavlo, who leads the Pechersk Monastery, is suspected of "inciting hatred".

Ukrainian authorities have sought to portray Russian Orthodox clerics in the country as supporting separatists.