Russia's new president, Dmitry Medvedev, warned on Thursday of "an adequate response" to US missile defence plans in Europe but said Moscow was still ready to negotiate with Washington.

"I don't think the situation is completely hopeless but those decisions that have been taken cannot please us and we will be forced to find an adequate response," Medvedev said in an interview with Chinese journalists posted on the Kremlin website.

But he added: "The worst thing would be simply to close the doors and windows and not to listen. That's why of course we are ready to continue negotiations on all tracks... with our European partners and American partners."

The United States has proposed to site a radar in the Czech Republic and interceptor missiles in Poland as part of a shield to defend against states it considers a threat, such as Iran and North Korea.

The Czech government approved the main radar plan on Wednesday.

Moscow has said it distrusts US motives and that the proposed missile shield threatens Russian security, being located close to Russian borders.

It has proposed creating a joint missile shield with Europe and the United States.

In leaving open the possibility of negotiations, Medvedev, in his first comments about the missile shield since taking over from Vladimir Putin this month, appeared somewhat less hawkish than his predecessor.

"We suggested to our US and European partners looking into creating a system of collective response to such threats... But unfortunately we have not had a positive response, although talks are continuing," Medvedev said.