By Peter Millership and Sayed Salahuddin

Washington/Kabul - President George W Bush outlined plans for the biggest rise in United States military spending in two decades for a protracted campaign to wipe out global terrorism, as captured American Taliban fighter John Walker Lindh arrived home to face trial.

As the United States expanded its war on terrorism beyond Afghanistan, Bush said he would propose a $48-billion boost in military spending for the 2003 financial year, the biggest rise in two decades, to help buy such items as precision weapons and unmanned vehicles.

"Our fight against terrorism began in Afghanistan, but it's not going to end there," said Bush. "We still face a shadow enemy who dwells in the dark corners of the Earth. Dangers and sacrifices lie ahead, yet America will not rest."

In Afghanistan, tribal rivalries, who are wary of US forces in the region now the Taliban militia has been defeated, threatened to complicate the imposing task of rebuilding the war-scarred nation while interim Afghan leader Hamid Karzai was in Beijing to meet Chinese leaders.

As US forces hunted for Osama bin Laden, blamed for the September 11 attacks which killed more than 3 000 people, a close associate of Taliban leader Mullah Mohammad Omar surrendered about 1 200 weapons.

And visiting the southern city of Kandahar, FBI Director Robert Mueller told CNN that data gleaned from prisoners and from documents had prevented attacks on US facilities.

The Pentagon, which has dismissed criticism of its handling of captured Taliban and al-Qaeda fighters, said it temporarily suspended flights of captives to a US navy base at Guantanamo Bay, Cuba, to expand jail space there.

The 158 prisoners being held were questioned on Wednesday for the first time.

"It's an interview process, an information-gathering process, not a forceful process," said Navy Captain Robert Buehn, commander of the navy base.

Under tight guard, Walker landed at Dulles airport to face trial on four charges that include conspiring to kill Americans abroad and providing support to Bin Laden's al-Qaeda.

The charges carry a maximum sentence of life in prison.

There were few details about the condition of Walker who was whisked from the airport by helicopter. One senior US defence official, who asked not to be identified, said: "He asked to have his hair cut and his beard shaved before he came over."

Lawyer James Brosnahan, hired by Lindh's parents shortly after their son's capture in Afghanistan, said they had been given a letter from Walker on Wednesday in which he said he was "comforted" to know that his family had hired a lawyer.

"The government clearly knew about this letter because it was penned by a member of the US military," said Brosnahan in a statement.

US Attorney General John Ashcroft said on Wednesday that Walker, 20, had repeatedly waived his right to an attorney both verbally and in writing during interrogation sessions.

Walker will appear in a federal court in Alexandria, Virginia, on Thursday. At the 9am (1400 GMT) appearance, the 20-year-old Californian, who joined Taliban fighters in Afghanistan last year, will be asked if he wants or needs an attorney. He will enter a plea at a later date.

Walker had been held aboard the US warship Bataan in the Arabian Sea. He was taken to the warship from a prison outside the northern Afghan city of Mazar-i-Sharif, where an uprising occurred during which CIA agent Mike Spann was killed.

In announcing charges against Walker last week, Ashcroft said charges of treason, which could bring the death penalty, would be difficult to prove but have not been ruled out.

With the US military using high-tech equipment to search for Bin Laden and Omar, warlord of the Noorzai tribe Haji Bashar, a close associate of Omar, gave up his firearms and 30 vehicles to Kandahar Governor Gul Agha in Maiwand district.

However, worries about the stability of the UN-backed administration grew after a report that forces loyal to fearsome ethnic Uzbek warlord General Abdul Rashid Dostum had seized a northern district after clashes with rival troops.

Forces battling for control of Qale Zaal district are linked to the two Afghan defence chiefs. The ethnic Uzbek force is under Dostum, deputy defence minister, and the rival ethnic Tajik force is loyal to Defence Minister Mohammad Fahim.

The Pakistan-based Afghan Islamic Press said several fighters on both sides were killed and wounded in the latest round of fighting that ended after Dostum's troops drove their rivals from Qale Zaal, 60km northwest of Kunduz.

In Turkey, Dostum pledged to back the interim government.

On another ominous note, Benazir Bhutto, former Pakistan prime minister, hoping to contest national elections this year, said on Wednesday that there was a risk Islamabad would try to destabilise the new government.

"Knowing the mind-set of the Pakistani establishment, I (comprehend) that there will be attempts sooner or later to destabilise the Karzai government which Islamabad privately considers as pro-Indian," said Bhutto in an email interview received on Wednesday.

More trouble loomed in the south where tribal leaders in Kandahar province vowed to clear neighbouring Helmand province of what they said were hostile fighters backed by Iran.

Provincial government spokesperson Abdul Ali said action was planned against western Herat warlord Ismail Khan.

Khan said by satellite phone that an assault on Herat would be a big blow to the peace process in the war-shattered country.

In another problem faced by Karzai, the United Nations said on Wednesday that lawlessness was hampering relief work in Afghanistan and crime was on the rise in Kabul despite an international security force there.

The force, organised by Britain and mandated by the United Nations, has a six-month lifespan but Abdullah Abdullah said he would consider asking it to stay on and even expand.

The force numbers 1 700 could rise to 5 000.

"If the circumstances of maintaining stability and security throughout the country required further presence of the multinational forces, we would go for it or even add the numbers to it," he said in Beijing.

China, wary about the presence of US troops in its backyard, is also keen to see a stable Afghanistan.

Chinese Premier Zhu Rongji said his country would do everything it could to help rebuild Afghanistan, while visiting Afghan leaders said they backed China's fight against Islamic separatists in its far west.

China says under the former Taliban regime, the country was a training ground for hundreds of Muslims connected to a small separatist movement in its far Western region of Xinjiang.

Afghan Foreign Minister Abdullah said authorities were certain there were links between the Xinjiang separatists, the Taliban and Bin Laden's al-Qaeda and offered China total co-operation on the issue. - Reuters