Former President George Bush (r) with an earthquake survivor from Leepa Valley of Pakistani Kashmir during his visit to quake survivors' tented village in Islamabad

U.N. special envoy, former U.S. President George H.W. Bush, has toured a tent camp in the Pakistani capital, Islamabad, housing the survivors of last year's devastating earthquake.

But winter weather prevented him from visiting Pakistani Kashmir's ruined capital, Muzaffarabad, and also grounded vital aid flights to survivors there for a third straight day.

At a joint news conference with Pakistan's Prime Minister Shaukat Aziz, Tuesday Mr. Bush said his role is to encourage those who have pledged relief and reconstruction aid to deliver on their pledges.

A U.N.-led relief operation is under way in Pakistan, but U.N. officials say the world body is still far short of the $500 million needed to sustain the effort.

The October 8 quake killed more than 73,000 people and left some three million homeless.