Russian coast guard ships on Sunday fired on and seized the Ukrainian vessels as they headed toward a contested strait close to Crimea, taking prisoner 24 Ukrainian sailors and triggering an worldwide crisis.
The Ukrainian church, which has been part of the Russian Orthodox Church for centuries, has moved closer to forming an independent church - fuelled by conflict with Russia Ukraine's Orthodox communities earlier this year.
According to the BBC, Russian President Vladimir Putin said Thursday the incident was "a provocation" organized by the Ukrainian government "in the run-up to the Ukrainian presidential election", which Poroshenko is expected to lose.
It has said the Ukrainians were violating Russian waters and that Ukraine did not inform Russian officials of its naval movements.
"(This is) to prevent Russians from implementing in Ukraine the operations that they planned in 2014", he added.
The explanatory note says that the current total of Russia's combat aircraft located along Ukraine's borders makes about 500 fighters and ground attack aircraft and 340 helicopters.
Poroshenko said that the ban on Russian male immigration is created to prevent a repeat of the 2014 Russian invasion of Crimea, in which nominally "private" commandos acting at the Kremlin's direction seized and occupied sovereign Ukrainian territory.
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Rising interest rates in advanced economies and trade tensions have increased pressures on emerging markets recently. The Group of 20 brings together leaders of 19 of the world's most industrialised nations plus the EU.
For Russia will not, whether out of security concerns or ambition, stop tightening the noose the Sea of Azov and the Kerch Strait represent for Ukraine.
Erdogan said he would hold more talks concerning the standoff with both Putin and U.S. President Donald Trump on the sidelines of the G-20 summit meeting in Buenos Aires.
Relations collapsed following Russia's seizure of Crimea from Ukraine in 2014 and the outbreak of a Kremlin-backed insurgency in eastern Ukraine that has killed more than 10,000 people.
On Sunday, Russian ships fired on and seized three of Ukraine's artillery ships, wounding six Ukrainian crew members.
"We are dismayed at this use of force by Russian Federation which, against the backdrop of increasing militarisation in the area, is unacceptable", European Union foreign policy chief Federica Mogherini said.
The travel restriction on Russian men would not apply in cases where they visit for "a funeral or some other humanitarian purpose", he said.
It has raised fears of a wider escalation - in a conflict that has killed more than 10,000 people since 2014 - and prompted global calls for restraint. Trump, who was en route to Buenos Aires for the G-20 summit, said he would not be meeting Putin because "the ships and sailors have not been returned to Ukraine from Russian Federation". Ukrainian authorities have sought to portray Russian Orthodox clerics in Ukraine as supporting separatists. Earlier this year, Russian Federation opened a bridge that connects mainland Russian Federation with annexed Crimea.
No one wants war, but this is how one gets a war.
Russia's foreign ministry responded to the temporary ban on Friday, criticizing Ukraine leadership and saying it would not reciprocate.