Kabul : The United States will ask Nato countries to step up their commitment to help Afghanistan recover from years of tyranny and war, US Vice-President Dick Cheney said on Thursday.

"We believe the commitment needs to continue and perhaps needs to be reinforced," Cheney said on a visit to the Afghan capital.

Standing beside Afghan President Hamid Karzai at a news conference, he also said neighbouring Pakistan had an obligation to battle insurgent activity along the border between the two countries.

He also sought to remind that the Pakistani government, like Karzai's, remained a target for the Al Qaida and other extremist groups. "They have as big a stake as anyone else," he said.

Cheney's remarks came after he met with Karzai at the Afghan leader's palace to discuss ways the country's fragile government could counter rising threats from Al Qaida and Taliban militants.

"During the last six years, the people of Afghanistan have made a bold, confident journey, throwing off the burden of tyranny and winning your freedom," he said with a nod to Karzai. "The process has been difficult, but the courage of the nation has been unwavering," he said, noting a remarkable progress in improving security forces and rebuilding efforts even as the country struggled in a continuing war with insurgents.

Karzai also hailed progress, saying the Afghan army was getting stronger "day by day", but adding that international support would be needed for years to come.

As for his own political future, Karzai declined to say whether he would seek another term as president in elections scheduled next year. He said he wanted to leave a legacy of strong political leaders in Afghanistan's future and that perhaps he could best achieve that by not running for re-election.

Gag on reporters

Cheney flew to the Afghan capital from Oman and took a helicopter straight to the presidential palace, where he greeted Karzai with a hearty handshake. The two strolled down a red carpet together, reviewing troops before heading off into the palace for their talks.

Reporters were not allowed to disclose Cheney's visit until he had arrived safely. It is Cheney's fourth vice presidential trip to Afghanistan. Cheney, who is on a 10-day foreign trip, visited Iraq earlier this week.

More than 8,000 people died in fighting in Afghanistan last year, making it the most violent year since 2001, when the US invaded the country to oust the hardline Taliban regime after the September 11 attacks back home.

Cheney spokeswoman Lea Ann McBride said US President George W. Bush had asked Cheney to meet with Karzai in advance of a Nato summit next month in Romania.

Problems in Afghanistan will be a key topic at the Nato summit. The alliance has about 43,000 troops in Afghanistan, but commanders have asked for more in areas to the south of the country where the insurgency is the most active.

Troops from Canada, Britain, the Netherlands and the United States have done the bulk of the fighting against Taliban militants. Forces from France, Spain, Germany and Italy are stationed in more peaceful parts of the country.

Call for pledging troops

Canada, which has 2,500 troops in Kandahar province, recently threatened to end its combat role unless other Nato countries provide an additional 1,000 troops to help the anti-Taliban effort there. Canadian Defence Minister Peter MacKay said he expected a pledge for troops before or during the April 2-4 Nato summit.

The US contributes one-third of the Nato force, and also has about 12,000 other troops operating independently from Nato. The Pentagon says that by late summer, there will be about 32,000 US troops in Afghanistan - up from about 28,000 now.