U.S. President George W. Bush's White House adviser on counterterrorism and homeland security has resigned, he announced on Monday, the latest in an exodus of top aides with 14 months left of his presidency.

Bush said in a statement that Fran Townsend has always provided wise counsel on how to best protect the American people from the threat of terrorism.

She has been a steady leader in the effort to prevent and disrupt attacks and to better respond to natural disasters, the president said. He gave no reason for her departure.

Townsend, who served 4-1/2 years in a post created after the September 11 attacks on the United States in 2001, had also been a prosecutor in New York and deputy national security adviser.

Her resignation adds to a list of high-profile departures from the administration in recent months.

Senior Bush adviser Karl Rove left in August, White House press secretary Tony Snow resigned in September and White House counselor Dan Bartlett stepped down in June. Attorney General Alberto Gonzales, another member of Bush's inner circle, resigned under pressure in August.

(Reporting by Matt Spetalnick; Editing by John O'Callaghan)

New York George W. Bush