Tensions surfaced on Sunday after Russia tried to intercept the three Ukrainian ships - two small armored artillery vessels and a tug boat - in the Black Sea, accusing them of illegally entering Russian territorial waters. He reportedly said he called the meeting, "to discuss unsafe Ukraine provocations in the sea of Azov and Kerch Strait near Crimea threatening worldwide peace and security".
British Prime Minister Theresa May's spokesman, James Slack, said the incident was "further evidence of Russia's destabilising behaviour in the region and its ongoing violation of Ukrainian territorial integrity". A spokesman for the FSB, the country's Federal Security Service - which oversees the coast guard - said the Ukrainian vessels violated territorial waters and had to be stopped.
But there is a hard balance to be struck between support for Ukraine's territorial integrity on the one hand and avoiding anything that might tip the conflict into full-scale war.
US Ambassador Ms Haley said she has also spoken with President Donald Trump and Secretary of State Mike Pompeo about Russia's "outlaw" actions.
Amid the Black Sea standoff, popular Russian TV host Dmitry Kiselyov told state television that Poroshenko was picking a fight with Russia at the prompting of the United States.
'From November 26, 2018, to enter into force the decision of the National Security and Defense Council of Ukraine on emergency measures to ensure the state sovereignty and independence of Ukraine and the introduction of martial law in Ukraine, ' reads the order.
Instead, the USA "will continue to stand with the people of Ukraine against the Russian aggression", she said, including through sanctions on Russia for its illegal annexation of Crimea.
Former U.S. Ambassador to Ukraine John Herbst believes that the attack by Russian forces against Ukrainian Navy vessels on November 25 was meant to provoke Kyiv into a strong military response that would give Moscow a pretext for a larger attack on Ukraine.
The Ukrainian Navy said that the "occupiers" dispatch service refuses to ensure the right to freedom of navigation, guaranteed by global agreements.
Ukrainian cities on the Sea of Azov include strategically vital centres such as Mariupol - the closest government-controlled city to Donetsk and Luhansk, the breakaway regions of eastern Ukraine controlled by Russia-backed separatists.
Russian Federation closed the Kerch Strait for sea traffic by positioning a cargo ship under the bridge spanning it.
Russia's control of Crimea, where its Black Sea Fleet is based, and of the bridge mean it is able to control shipping flows.
They then boarded and seized all three vessels, capturing 23 Ukrainian sailors, in an operation involving attack helicopters and fighter jets.
But Russia is already heavily sanctioned, and this has not encouraged it to rethink its annexation of Crimea.
He said: "Clearly the Russians were prepared to act as they have and it had been cleared at high levels in Moscow, but the actual timing was driven by the fact that the Ukrainians were trying to increase their naval presence in the Sea of Azov".
After the incident in the Black Sea when a Russian coast guard vessel rammed a Ukrainian navy tugboat, Moscow begins deployment of its troops to an area of Kerch bridge. "It will further sour Russia's relations with the US and many other countries".