ISLAMABAD: Sen. John McCain expressed his concern on Friday about “harassment of US diplomats in Pakistan” and said this is affecting Pakistani-US relations.

Addressing a news conference here, he said: “Our diplomats for security reasons use vehicles with local registration numbers and their task is to visit social sector developmental projects.”

McCain is touring Pakistan at the head of a four-member congressional team. He is accompanied by Sen. Joseph Lieberman, Sen. John Barrasso and Sen. John Thune.

McCain said the US Embassy complained to the visiting US congressmen on Thursday that its staff members are being harassed and detained as they travel around Pakistan. “Our staff here is merely supervising social sector developmental projects.”

McCain defended US drone attacks on militants inside Pakistan. “The use of drone strikes against militants in Pakistan is an effective part of US strategy and should continue,” he added

“We don’t agree on every issue. We believe that, as I have stated and as our government has stated, that it is one of many tools that we must use to try to defeat a very determined and terrible enemy,” added McCain.

There have been a high number of pilotless drone aircraft attacks in Pakistan since a double agent blew himself up at a US base in Afghanistan on Dec. 30, killing seven CIA agents. The United States sees the drones as a highly effective weapon in a global hub for militants. The strikes have killed some prominent Al-Qaeda militants. Pakistan has objected to US drone strikes on its soil as that puts the government in poor light.