Russian president Vladimir Putin has raised tensions over controversial US plans to install a missile defence shield in Poland and the Czech Republic by threatening to target Russian missiles at Europe.

Speaking to reporters ahead of this week’s G-8 meetings, Mr Putin said Russia would have to respond to the threat of US missiles in Europe. The US says the missile shield – which would involve installing 10 missile interceptors in Poland and a radar in the Czech Republic – is aimed at protecting the US and Europe and Iranian missiles.

“It’s obvious that if part of the strategic nuclear potential of the US is located in Europe, which in the opinion of our military experts represents a threat, we will take the corresponding steps in response,” said Mr Putin, according to a transcript of the interview with the reporters posted on the Wall Street Journal’s website.

“Of course we will have to get new targets in Europe,” added Mr Putin.

While senior Russian generals have previously made the same threat, this was the first time that Mr Putin endorsed such a move publicly.

His comments come as President George W. Bush arrives in Europe for an 8-day visit that includes the G-8 summit in Germany. Mr Bush last week attempted to lower tensions by saying “the Cold War is over”. But Mr Putin heralded a return to the Cold War era when the US and Russia both had missiles aimed at each other.

Mr Putin also criticised the US plans, saying they were unilateral, and had not received formal European approval.

“We are told that it’s for the defence of Europe. Has anyone asked Europe? Was there some kind of general European decision or even a decision in NATO, even for appearance’s sake?” said Mr Putin. “No. They didn’t want to ask anyone.”

Tensions between Washington and Moscow have been on a downward spiral since Mr Putin lambasted US foreign policy in a February speech in Munich to defence policy elites, including Mr Gates. While the US has attempted to play down the differences, Mr Putin’s comments will likely ensure that Russia remains close to the top of the G-8 agenda.

Russia has not been swayed by a series of meetings with senior US officials, including Robert Gates, the defence secretary, over the missile defence system. Mr Gates in April visited Moscow in an effort to reassure Mr Putin that the system was not directed at Russia, and also to reduce fears in Europe about a growing rift with Russia over the shield.

Condoleezza Rice, the US secretary of state, has also attempted to convince the Russians that the system is aimed at rogue missile threats, especially from Iran. Russia argues that Iran does not pose a threat.

“How is it being explained? That it is necessary to defend oneself against Iranian missiles,” said Mr Putin. Iran does not have missile with a range of 5-8,000km…It’s a defence against something which does not exist. It would be funny if it was not so sad.”

Mr Putin said Russia was trying “to be heard”, adding that he did not rule out the possibility that the US would reverse its decision. Poland and the Czech Republic have yet to formally agree to host the missile interceptors and radar.