Ukrainian officials on Friday upped the ante in the growing confrontation with Russia, announcing a travel ban for most Russian males and searching the home of an influential cleric of the Russian Orthodox Church.
Earlier, in a move applauded in Kiev, U.S. President Donald Trump called off a meeting with Russia's Vladimir Putin in Argentina to signal Washington's disapproval of Russian behavior in the naval clash with Ukraine.
Ukraine has said the incident was a flagrant violation of worldwide law, while Russian Federation say the vessels violated its territorial waters.
Ukrainian vessels, including warships, would have to notify Russian authorities before passing beneath the Kerch Strait Bridge into the Sea of Azov to reach their major port of Mariupol.
Fighter jets and attack helicopters were deployed to assist Russian vessels, which chased the Ukrainian ships down, rammed one and opened fire on all three.
The Ukrainian parliament on Monday also adopted a motion from Poroshenko to impose martial law in the country for 30 days in the wake of the standoff.
In particular, speaking at a presser on Friday, answering the question whether a possibility is being considered to transfer Russian diplomatic institutions from Kyiv and Lviv to the occupied Donbas amid constant rallies outside these institutions, spokesperson for Russia's Foreign Ministry Maria Zakharova said: "Regarding what you asked, if there was any idea to transfer these institutions".
Fighting between Ukraine and Moscow-backed separatists has killed more than 10,000 people.
White House Press Secretary Sarah Sanders said Tuesday that Trump will meet his Russian counterpart Vladimir Putin during the upcoming G20 summit.
President Petro Poroshenko said Ukraine risked “full-scale war with Russia”
Her comments follow the seizure of Ukrainian ships by Russian Federation on Sunday which has prompted Ukrainian President Petro Poroshenko to argue for further pressure being put on Moscow.
Nato, which has condemned Russia's seizure of the Ukrainian ships, said that the alliance's ships routinely patrolled and exercised in the Black Sea, that allies conducted regular air policing and reconnaissance flights there, and that the alliance had stepped up its activities since Moscow annexed Crimea.
"Europe is united in its support to Ukraine's sovereignty and territorial integrity".
Meanwhile, Ukraine's intelligence agency announced on Friday that it is investigating a senior cleric of the Russian Orthodox Church. Now, it's moving close to forming an independent church, a momentous step pushed by Poroshenko that would split the world's largest Orthodox denomination.
There are now three Orthodox communities in Ukraine, including two breakaway churches. One is heard saying "the actions of the Ukrainian armed vessels in the Kerch Strait had a provocative character" - parroting the version put forward by Russian authorities.
The confrontation took place on Sunday in the Kerch Strait when the Ukrainian ships sailed from Odessa to Mariupol, in the Sea of Azov, an area shared by the two countries. Since then, a freighter ship has blocked the only entrance in and out of the waterway.
"We have to be clear and unequivocal because I think we're being tested - not just us but the [European Union] and others interested in the rule of law", Sen. She said she met with some of them and they appeared to be in good shape.
On Wednesday, Crimean courts imposed two-month pre-trial detentions on all 24 Ukrainian sailors, who are suspected of breaching the Russian state border (part 3, Article 322 of the Russian Criminal Code).