Russia threatened on Thursday to pull out of a landmark nuclear arms control treaty unless the US backed away from plans to install its missile defence shield in Eastern Europe.

Yury Baluyevsky, the Russian army chief of staff, said Moscow might unilaterally withdraw from the 1987 Intermediate-range Nuclear Forces treaty, which forced the US and the Soviet Union to ban nuclear and conventional ground-launched ballistic and cruise missiles with ranges of 500 to 5,500km.