Karzai heads to US for anti-terror summit

Afghan President Hamid Karzai headed to Washington Monday to meet US leader Barack Obama and Pakistan's Asif Ali Zardari amid concerns about efforts to fight the Islamist threat in the region.

Karzai flew to Washington with his foreign and defence ministers immediately after registering to run for a second term in August presidential elections, including on his ticket controversial warlord Mohammad Qasim Fahim.

Karzai was due to meet the US and Pakistani presidents on Wednesday, a statement from his office said, announcing his departure.

He would also meet other US officials, including House of Representatives speaker Nancy Pelosi, and deliver an address to the prominent Brookings Institution on "effective ways of fighting terrorism", the statement said.

Obama has put the spotlight firmly on Taliban and Al-Qaeda extremists straddling the Afghan and Pakistan border, pledging more troops and resources to eliminate what he has called an international threat.

He has also pushed for more cooperation between the Islamic neighbours to deal with the militants, expressing concern about the fragility of Pakistan's eight-month-old civilian government which has made concessions to the Taliban.

Secretary of State Hillary Clinton said recently the US administration would have "some very intense sessions" with the Afghan and Pakistani delegations on Washington's new strategy in the region.

The three-way format is "quite helpful at beginning to change mindsets and, frankly, set forth some requirements about what we expect from these governments," Clinton said.