Poroshenko wrote on Twitter that he declined to impose martial law for 60 days to avoid affecting residential election campaigns.
"It is an arrogant act that the worldwide community must condemn and will never accept", Haley said.
The United Nations Security Council and North Atlantic Treaty Organization have urged restraint from both sides.
Russian state media has reported the confrontation is a provocation orchestrated by Ukraine and others in America to disrupt the forthcoming meeting between Russian President Vladimir Putin and President Donald Trump at the G20 Buenos Aires summit this week.
Canada joined its allies Monday in condemning Russia's seizure of three Ukrainian naval vessels near Crimea, but experts are divided on what the sharp escalation of the deadly and protracted conflict will mean.
At one point in the footage, one of the sailors is heard saying, "The actions of the Ukrainian armed vessels in the Kerch Strait had a provocatory character".
ATP Finals: Ball boy flub gives Alexander Zverev edge over Roger Federer
He added that Anderson was "1010% wrong" for blaming him and that his honor would prevent him from clouding the truth. I don't know, Paris [Masters - against Novak Djokovic] or Wimbledon [against Kevin Anderson ].
Russian Federation claimed that Ukraine didn't inform them that the ships would enter the area, and that they were trying to ratchet up trouble.
As world leaders denounced Russia's aggression against Ukraine, President Donald Trump waited more than a day before offering a muted response about the clash, leaving the task of criticizing Moscow to the outgoing United States ambassador to the UN.
Russia's Federal Security Service, known as the FSB, told Russian news agencies Sunday after the first incident that the Ukrainian ships held their course and violated Russian territorial waters.
For reference. Article 17 of the UN Convention provides that, subject to compliance with the Convention, vessels of all states, both coastal and landlocked, enjoy the right to peaceful passage through the territorial sea.
Russia's Gazprom and Ukraine's Naftogaz are also locked in a bitter dispute over payments for gas supply, with a court battle still going on.
Moscow claimed that the Ukrainian ships had illegally entered Russian territorial waters. Analysts said Moscow was now trying to spark a conflict in order to show Ukraine's leadership that it could act with impunity. The Foreign Ministry also said it warned Ukraine and "its Western sponsors" many times about "the dangers of artificially inflated hysteria" in the Azov Sea and at the Kerch Strait.
The Ukranian vessels were sailing between two Ukrainian ports: from Odessa in the Black Sea to Mariupol in the Azov Sea.
In 2014, Ukraine's pro-Russian leader was overthrown, after large-scale protests against the government's decision to abandon plans to sign an association agreement with the EU.