ISLAMABAD, Pakistan - Pakistan's main spy agency has given India information about the Mumbai terror attacks, the prime minister said Friday, while denying media speculation of a rift between him and the president.

The comments came as U.S. Vice President-elect Joe Biden arrived in Pakistan for talks with the country's top military and political leaders. The U.S. Embassy confirmed the visit but gave few details.

Pakistan's fight against al Qaeda and the related insurgency in neighboring Afghanistan will be a major foreign policy concern for the incoming U.S. administration.

South Asia's importance in the anti-terror fight was underscored by the November attacks that killed 164 people in Mumbai. New Delhi says it has passed on evidence to Islamabad that proves Pakistani militants were behind the slaughter.

Pakistani Prime Minister Yousuf Raza Gilani told reporters the country's premier spy agency, Inter-Services Intelligence, "had given feedback and information sharing that has been passed on to India" after studying that evidence. He gave no more information.

On Wednesday, Gilani fired the national security adviser hours after the official told reporters the sole surviving Mumbai attacker was a Pakistani citizen -- something that Islamabad had previously been unwilling to acknowledge.

Local media reported President Asif Ali Zardari was not informed of the decision, intensifying earlier media speculation of a split between the country's top two leaders.

"There is no misunderstanding," Gilani insisted to reporters Friday while denying reports that Zardari had expressed displeasure with the decision.

A spokesman for Zardari said Thursday that the two were "on the same page" and it was Gilani's prerogative to fire the adviser, Mahmood Ali Durrani.

The Mumbai attackers are suspected to be members of Lashkar-e-Taiba -- a militant group created by Pakistani intelligence agencies in the 1980s to fight Indian rule in Kashmir, a Himalayan region claimed by both countries and the trigger for two of their three wars.

Some analysts say the group maintains ties to Pakistani intelligence and the government cannot act too aggressively against it as a result.

In recent weeks, several U.S. envoys have visited India and Pakistan to defuse tensions between the nuclear-armed neighbors and press Islamabad to take action against extremists on its soil.

Biden is traveling to Pakistan in his capacity as a U.S. senator. He is being accompanied by U.S. Sen. Lindsey Graham. Biden takes office as vice president on Jan. 20, but has not yet resigned his Senate seat.