Russia said on Friday it was seeking clarification of "unexpected" remarks by a senior U.S. defence official that the United States was considering Ukraine as a place for stationing early warning radar systems, Reuters reported. Alexander Vershbow, a U.S. assistant secretary of defence, was quoted in the magazine Defence News as saying Washington had added Ukraine to the list of possible early warning sites as part of its refashioning of a European missile defence system. Russian Foreign Minister Sergei Lavrov, who was attending a summit of the Commonwealth of Independent States in the Moldovan capital, said: "The statement by Alexander Vershbow was rather unexpected. In principle, he is a person who is prone to extravagancies. "We would like to receive full clarification," Lavrov told journalists. Lavrov meets U.S. Secretary of State Hillary Clinton in Moscow on Oct. 13 and it seemed certain that he would bring up Vershbow's comments then. He earlier told journalists that European missile defences was one of the issues he wanted to discuss with Clinton as well as progress between the two former superpowers on strategic nuclear weapons cuts. U.S. President Barack Obama's administration last month dumped Bush-era plans for a missile shield in eastern Europe to the delight of Moscow which had seen the project as a threat to Russian national security. That plan had foreseen stationing of parts of the anti-missile shield in Poland and the Czech Republic. A redrafted U.S. anti-missile plan that would target small and medium-range missiles from other countries has won a cautious welcome from Russia though Moscow awaits real detail on the project. It was not immediately clear how Moscow would feel about early warning radars being placed in Ukraine, a former Soviet republic which has in the past four years slipped further away from Russia's sphere of influence. Russia fiercely opposes the pro-Western policies of Ukrainian President Viktor Yushchenko, particularly his ambition to take Ukraine into the U.S.-led NATO alliance in the future. Stationing of U.S. anti-missile systems there could be seen in Moscow as a deepening of Ukraine's integration into NATO structures. In Kiev, newly appointed Ukrainian Foreign Minister Petro Poroshenko, asked about the report that the United States sought to station missile systems in Ukraine, replied: "I think this is not constitutional."