A Pakistani watches the live nationwide television address of President General Pervez Musharraf at a shop in Islamabad

Pakistan's President Pervez Musharraf has expressed regret over delays in earthquake relief efforts, saying the tragedy is much bigger than the government could handle.   The quake struck Pakistan on Saturday and has left 23,000 confirmed dead amid fears the final toll will be far higher.

In a televised address to the nation late Wednesday,  President Musharraf defended his government's slow response to the earthquake, which has killed tens of thousands and left an estimated 2.5 million people homeless. He asked his countrymen to be patient and reminded them the earthquake occurred in the most remote, inaccessible area.

He said the delay in providing relief was mainly due to the fact that roads were blocked and the administration in the affected area itself was among the victims.

The seven-point-six magnitude earthquake flattened towns and villages across the Pakistan-controlled portion of Kashmir and in neighboring North-West Frontier Province.

President Musharraf said the relief operation is now in full swing and thanked the international community for swiftly sending aid.

Condoleezza Rice (file photo)

"We have been given a lot of donations," said Mr. Musharraf.  "We have been given assistance in the relief and rescue operations, and several medical teams and field hospitals have been established by various countries of the international community. May I also say that the Indian prime minister was very kind to ring me up and offer all possible assistance."

But he appealed for more assistance, both from Pakistanis and from overseas, saying the reconstruction is expected to cost hundreds of millions of dollars.

So far, Pakistan has received pledges of $350 million from abroad.

During her brief visit to Islamabad on Wednesday, U.S Secretary of State Condoleezza Rice promised more assistance to Pakistan, a key U.S ally in the war against terror.

"The United States will want to support, along with the international community, the people of Pakistan," she said.  "And I just want the people of Pakistan to know that our thoughts are with you, that we will be with you in your hour of need and that we will be with you not just today, but also tomorrow as you try to rebuild."

The United States already has pledged $50 million and has sent several helicopters to help in the relief operations.  More U.S military helicopters are due to arrive this week.