World leaders and the diplomatic fraternity have condemned Russia's seizure of three Ukrainian navy ships, which were sailing around a waterway linking the Azov Sea and the Black Sea, and detention of 24 sailors on Sunday.
US ambassador to the UN Nikki Haley on behalf of America, the Netherlands, Poland, Sweden, and the UK on Monday told the Security Council they jointly strongly support Ukraine's sovereignty and territorial integrity.
This was followed by a tweet from the mission's Twitter handle: "This is no way for a law-abiding civilised nation to act. Impeding Ukraine’s lawful transit through the Kerch Strait is a violation under international law. It is an arrogant act that the international community must condemn and will never accept."
Secretary of State Mike Pompeo called for the return of Ukrainian vessels and crew members, respect for Ukraine’s sovereignty and territorial integrity.
Ukrainian lawmakers on Monday voted to introduce martial law.
Ukraine President Petro Poroshenko, in a tweet, said martial law would be introduced in regions bordering Russia, or adjacent to regions where Russian troops are posted.
This followed the approval by the National Security and Defense Council of Ukraine to offer President Poroshenko the introduction of martial law for a period of 60 days, starting November 28.
"The NSDC considers it necessary to introduce a special legal regime in Ukraine to create conditions for repelling armed aggression and ensuring national security, eliminating threats to independence and territorial integrity of Ukraine," a correspondence seen by the Star said.
Ukraine's Foreign ministry said the attack is "nothing but another act of armed aggression of the Russian Federation against Ukraine, as defined, in particular, in Article 2 of the Charter of the United Nations and the provisions of UN General Assembly Resolution 29/3314 of 14 December 1974 on the definition of aggression."
However, Russia says Ukrainian navy ships violated rules for the peaceful passage of ships travelling to the Black Sea through Russia’s territorial sea, and that "Ukraine is solely responsible for any negative developments that may take place after Kiev created a conflict situation in the Sea of Azov and the Black Sea area."
According to Russian news Agency, the Russian Foreign Ministry summoned Ukraine’s Charge d’Affaires to Moscow Ruslal Nimchinsky on Monday and handed a note of protest against the November 25 incident.
The European Union, through its spokesperson Moja Kocijancic on Monday said Russia should restore freedom of passage at the Kerch Strait and urged the parties to "act with utmost restraint to de-escalate the situation immediately".
"The EU does not and will not recognise the illegal annexation of the Crimean peninsula by Russia."
Reacting to the escalating tensions in the Azov Sea and Kerch Strait, Lithuania President Dalia Grybauskaitė tweeted, "Strongly condemn #Russian aggression against #Ukraine. Capture of Ukrainian vessels in #KerchStrait - another blatant violation of international law and Russia‘s own commitments."
Estonia Prime Minister Jüri Ratas said the incident is a serious breach of international law.
"I condemn Russia's seizure of Ukrainian naval vessels, blocking of the Kerch Strait and aggression against Ukraine. I support the European Union and NATO's call for a de-escalation of the tense situation".
Romania Foreign Affairs ministry in a tweet said: "Deeply concerned about the developments in #AzovSea & #KerchStrait. Aggression and violation of international law undermine the security of the whole region. #RO fully supports the territorial integrity and sovereignty of Ukraine and its rights to use its territorial waters."
Canada Foreign Affairs Minister Chrystia Freeland also condemned the action saying,"Canada condemns Russian aggression towards #Ukraine in the #KerchStrait. We call on #Russia to immediately de-escalate, release the captured vessels, and allow for freedom of passage. Canada is unwavering in its support for Ukraine’s sovereignty.
Australian embassy in Ukraine said it was concerned by the developments in the Sea of Azov, and that it fully supports Ukraine's sovereignty and territorial integrity, and call on Russia to restore navigation rights at the Kerch Strait
Moscow must ensure access to the Sea of Azov, German Europe Minister Michael Roth said on Monday.