Russia says it is asking Bulgaria to explain its plans to deploy¹ US air defence missiles on its soil.

俄罗斯要求保加利亚计划在其国土上部署美国的导弹防御计划进行解释。

The US says its missile shield is not directed against Russia  

The move follows reports that talks between Sofia and Washington on hosting elements of the US missile shield in Bulgaria have already begun.

According to a Russian foreign ministry² statement, Moscow would be sending an official query³ about the "aims and existence of such talks".

Last week the Bulgarian prime minister said he was keen to join the US shield.

At a meeting in Moscow on Thursday, Russian Deputy Foreign Minister Vladimir Titov told Bulgaria's ambassador to Russia, Plamen Grozdanov, it would seek an explanation as to the "goals and essences" of its talks with the US.

Russian Foreign Minister Sergei Lavrov has already asked for an explanation from the US about its missile defence plans.

Over the past days details have emerged of America's offer to Romania and Bulgaria.

Washington is thought to envisage⁴（面对，想象） sea-based interceptor（拦截机） missiles on US ships in the Black Sea from as early as next year, and land-based missiles from 2015.

The plans have drawn⁵ sharp criticism from Moscow, where officials described an earlier project to base radar⁶ and missiles in the Czech Republic and Poland as a threat to Russia.

Washington says the missile shield is designed to protect against short- and medium-range missiles from Iran, and is not directed against Russia.

Earlier this week Moldova's breakaway（分离，逃脱） region of Trans-Dniester reacted to Washington's plans by offering to host new Russian missiles.

Trans-Dniester leader Igor Smirnov said Russia had not yet asked it to be a host, but any request would be approved.