Washington: Secretary of State Hillary Rodham Clinton says the United States expects more cooperation in fighting terror from the Pakistan government and warned of repercussions if a future successful attack in the United States were to be linked to Pakistan.

In an interview with CBS television's "60 Minutes" to air this weekend, Clinton says that Pakistan has become far more helpful in battling extremists during the past year, but cooperation could be improved.

She says the Obama administration has made it clear there will be "severe consequences" if an attack on U.S. soil were to be traced back to Pakistan.

US Defense Secretary Robert Gates also said Pakistan has recently stepped up efforts to root out extremist militants.