Richard Meserve, the chairman of the Nuclear Regulatory Commission (NRC) said he will resign from the agency at the end of March, over a year before his term expires. President Bush will nominate his replacement on the five-member commission and name a new chairman. The nomination requires Senate confirmation.

Meserve, selected for the post and made chairman by president Clinton in 1999, said he would become president of the Carnegie Institution, a prominent research centre. Meserve leaves at a time when the NRC is facing the challenges of protecting nuclear power plants from terrorist attack and approving the Yucca Mountain waste disposal site.

Meserve is one of three Democrats on the NRC. Commissioner Greta Joy Dicus, another Democrat, is expected to depart in June when her term expires.