Ukraine has banned most Russian men from entering the country as part of security measures imposed after Moscow's forces seized three of its ships and their crew in the Sea of Azov.
Ukrainian president Petro Poroshenko said the ban on Russian men aged 16 - 60 years was intended to "stop Russia forming squads of private armies here, which are actually representatives of the Russian armed forces, so they can't conduct the kind of operations that they tried to conduct in 2014."
He seemed be referring to pro-Russian protests in spring and summer 2014 that in some places led to demonstrators seizing state buildings. Kiev accused Moscow of sending agents and gangs of young men to such rallies to foment violence, which in the eastern Donbas region spiralled into a war that still rumbles on.
Ukrainian officials say Russians made 1.5 million trips to the country last year, and Moscow's foreign ministry spokeswoman, Maria Zakharova, called the ban a result of "wild movements by the leadership" in Kiev.
“The somersaults that we see today in Ukraine – that’s the complete dysfunction of the state structure,” she said.
Crisis deepens
The latest crisis has deepened Moscow's rift with the West over Ukraine, and US president Donald Trump said he had cancelled Saturday's planned talks with Russian counterpart Vladimir Putin due to his failure to free the ships and crewmen.
"This is how great leaders act!" Mr Poroshenko tweeted after Mr Trump announced that he would not meet Mr Putin at the G20 summit in Argentina, where German chancellor Angela Merkel plans to discuss Ukraine with the Russian leader.
Most of the captured crewmen have been transferred from Crimea, which Russia annexed from Ukraine in 2014, to prisons in Moscow where they face detention on suspicion of illegally crossing the Russian border.
The men were held last Sunday, when Russian ships fired on and captured their boats after preventing them from sailing through the Kerch Strait from the Black Sea to reach a Ukrainian port on the Sea of Azov, which the two states share.
Martial law
Kiev calls the incident an act of aggression, while Moscow claimed it was the result of a “provocation” to boost the popularity of Mr Poroshenko ahead of elections next March.
Ukraine imposed martial law on Wednesday in 10 border and maritime regions, to prepare for what Mr Poroshenko called the threat of “full-scale war” with Russia, which he claims is massing tanks near his country’s frontier.
Mr Poroshenko insists the impact of martial law on civilian life will be minimal, but Ms Zakharova called the measures “a serious danger” which could cause the war in eastern Ukraine to “engulf the entire country”.
Tension with Moscow is also building as Ukraine moves towards securing independence in religious affairs from the Russian Orthodox Church, in a process overseen by the Ecumenical Patriarchate in Istanbul – "first among equals" in the Orthodox world.
Agents from Ukraine’s security service on Friday raided the residence of a senior pro-Moscow cleric who leads Kiev’s oldest monastery, as part of an investigation into the incitement of religious hatred.
