Tokyo: International donors pledged more than $5 billion in fresh aid on Friday to Pakistan, seen as a frontline state in the battle against extremism.

The pledges, bigger than an expected $4 billion, reflect the international community's worries that an economic meltdown in Pakistan, propped up with a $7.6 billion loan from the International Monetary Fund over two years, could fan popular support for Al Qaida and other militant groups.

"The participants also noted concern about the security situation in Pakistan and the impact on development, the investment climate, and growth," co-chairs Japan and the World Bank said in a statement.

Matching a pledge from Japan, the US said it would provide $1 billion in aid over two years. The UAE pledged $300 million over two years. Announcing the pledge at the conference, Shaikh Abdullah Bin Zayed Al Nahyan, Foreign Minister, said in Tokyo that the move comes in line with the instructions of President His Highness Shaikh Khalifa Bin Zayed Al Nahyan to assist Pakistan.

"There are good projects and developmental programmes presented by Pakistan [but] the country's security and stability must be restored to take advantage of its huge opportunities," Shaikh Abdullah said. He added that "our presence at the conference signals the UAE's support for Pakistan" and was an indicator that the UAE leadership links the stability of Pakistan with Afghanistan.

Pakistan's President Asif Ali Zardari vowed to fight extremism and told donors that terrorism "does not end on my border. If we lose, you lose. If we are losers, the world is a loser." The new aid is targeted for areas such as health, education, governance and building democracy.

But underscoring the challenges ahead, the recently bailed head of Islamabad's Red Mosque called on Friday for the enforcement of Islamic law across Pakistan during his defiant return to his prayer hall, where at least 100 died when Pakistani troops stormed the complex in 2007.

"The day is not far away when Islam will be enforced in the whole of the country," Maulana Abdul Aziz said during Friday prayers.