U.S. Senator John Kerry has advised senior officials of the Pakistani government that he wants Islamabad to be a “real” ally and help with the fight against militants and terrorists.

On a trip to Afghanistan (ahead of a visit to Pakistan), Kerry cautioned that “serious questions” remain about relations between Washington and Pakistan after the discovery and killing of Osama bin Laden in the country.

“We obviously want a Pakistan that is prepared to respect the interests of Afghanistan, and to be a real ally in our efforts to combat terrorism,” Kerry told reporters in Mazar-i-Sharif in northern Afghanistan.

“We believe there are things that can be done better. And there are serious questions that need to be answered in that relationship. But we’re not trying to find a way to break the relationship apart, we’re trying to find a way to build it.”

Kerry was asked if the US would consider a similar bin Laden-type commando raid against another most-wanted terrorist, Taliban chief Mullah Omar, who is also rumored to be hiding out in Pakistan after fleeing Afghanistan after the 2001 US invasion.

“The United States government will always reserve all of its options to be able to protect our people. Other plots have been conducted and organized and planned out of Pakistan. It is really critical that we talk with the Pakistanis as friends,” Kerry said.

Pakistani officials have denied Omar is in their country.

Relations between the US and Pakistan are at an all-time law, with some prominent American politicians calling for a review or even suspension of aid to Islamabad.

Kerry, a Democrat and the chairman of the Senate Foreign Relations Committee, himself said last week that he found it “extraordinarily hard to believe” that the former al-Qaeda terror chief could have resided in Pakistan for so many years without the knowledge of Pakistani intelligence and security officials.

Pakistan has repeatedly denied the double-barreled allegations that it was either complicit in harboring bin Laden or was too incompetent to find him.

However, Kerry added that the death of bin Laden may now open a new chapter in the difficult relations between the U.S. and Pakistan, noting that Pakistani is itself a victim of terrorism.

“Sometimes those choices can be very difficult for people to make because of the pressures that they’re under and the violence that occurs,” he said.

“We respect and understand that, but this is the time, this is a critical time to find a better way forward and we hope that we’re going to be able to do that.”