Updated

One of the main front-runners in the race to succeed Afghan President Hamid Karzai tells The Associated Press that he will sign a security agreement with the United States within a month if he wins the race.

Abdullah Abdullah criticized Karzai for refusing sign the deal, which would pave the way for international forces to keep a residual force in Afghanistan after withdrawing combat troops by the end of 2014.

He said Thursday that at the "maximum it has to be signed within a month" if he becomes president.

Abdullah, who was the runner-up to Karzai in disputed 2009 elections, also expressed concern about fraud in the April 5 election.

Observers say none of the 11 candidates is expected to get a majority. A runoff vote is widely expected.