KIEV, March 18 (Xinhua) -- Ukraine on Tuesday appealed to the Budapest Memorandum guarantor countries to set up an emergency commission to de-escalate the ongoing crisis in the country.
"We need to convene an urgent commission of the defense ministries of Russia, the United States and Britain to prevent the escalation of the conflict," Ukrainian Prime Minister Arseny Yatsenyuk said in a statement.
Yatsenyuk said that Russian military troops opened fire on the Ukrainian armed forces earlier in the day, moving "political confrontation between the two countries into military direction."
"Russia had violated the rights of the Ukrainian state," Yatsenyuk said, urging the guarantors of the Budapest treaty to mediate the standoff between Kiev and Moscow through the political dialogue.
Earlier in the day, at least one Ukrainian serviceman was killed and another was injured in the clashes with allegedly Russian military forces in the Crimea.
The clashed came shortly after the leaders of Crimea signed a treaty with Russian President Vladimir Putin on the peninsula's integration into Russia.
In 1994, Kiev signed the Budapest Memorandum, under which Ukraine gave up its nuclear weapons in exchange for a guarantee of recognition of its sovereignty.
Russia, the United States and Britain, as guarantors of the treaty, are obliged not to use force against Kiev and mediate if a threat to Ukraine's territorial integrity arises.