A group of hardline officials known as "nuclear hawks" is being promoted in a shake-up of the Bush administration's arms control and non-proliferation teams, according to officials close to the administration.

The latest appointment, announced by President George W. Bush yesterday, saw Jack Crouch, the ambassador to Romania, become deputy national security adviser. Mr Crouch, who served in the Pentagon from 2001 to 2003 as assistant secretary of defence for international security policy, has a long background in arms control. In his Senate confirmation hearing in 2001 he was questioned on his support for US testing of nuclear weapons, his 1995 recommendation for destruction of North Korea's nuclear complexes in the absence of a satisfactory agreement, and the mistake he said was made by George H.W. Bush when president in withdrawing US nuclear weapons from South Korea.