President Barack Obama has announced a major overhaul of the US missile defence system in Europe. The US will shelve its controversial plan to build a defence system in Poland and the Czech Republic after a review of the threat from Iran. Czech Prime Minister Jan Fischer said Mr Obama had notified him of the change of plan. The US decision marks a major foreign policy shift which could impact on its dealings with Europe, Russia and Iran. On the military side, the decision would herald a shift of emphasis in the whole US anti-missile defence strategy. Russia, which saw the missile plan as a threat, welcomed the news but the move has already drawn criticism in the US.br/br/The US signed a deal in August 2008 with Poland to site 10 interceptors at a base near the Baltic Sea, and with the Czech Republic to build a radar station on its territory. The US had said the missile shield would be fully operational by 2012 to protect European allies and US forces in Europe from Iran or other countries.