Kabul, Dec. 15 : Two days after British Prime Minister Gordon Brown''s visit to Afghanistan, US President George W Bush arrived in Kabul on a surprise visit to address American troops at the Bagram Air Force base and for talks with his Afghan counterpart, President Hamid Karzai.

Bush flew into Afghanistan from Iraq, where a news conference was disrupted when an Iraqi TV journalist threw his shoes and shouted insults at him.

Iraqi television journalist Muntadar al-Zaidi stood up and shouted "this is a goodbye kiss from the Iraqi people, dog," before hurling a shoe at Bush which narrowly missed him.

With his second shoe, which the president also dodged, Zaidi, a correspondent for Cairo-based al-Baghdadiya TV, said: "This is for the widows and orphans and all those killed in Iraq."

The president ducked as the shoes hit the wall behind him. A BBC report said that the journalist was immediately wrestled to the floor by security guards. Bush joked afterwards that it was size ten shoe that was thrown at him.

During his visit in Iraq Bush signed a new security pact with Prime Minister Nouri Maliki, which paves the way for the withdrawal of US troops from Iraq by 2011.

"The work hasn''t been easy but it''s been necessary for American security, Iraqi hope and world peace," he said during talks with President Jalal Talabani.

The Iraqi leader called Bush "a great friend for the Iraqi people, who helped us liberate our country".

On arriving at the Bagram Air Force base, which lies north of Kabul, on Sunday, Bush was received by General David McKiernan, the US commander of NATO-led troops in Afghanistan.

He was then led into a giant white tent, where hundreds of US troops greeted him with cheers as he thanked them for serving.

"I am confident we will succeed in Afghanistan because our cause is just. Afghanistan is a dramatically different country than it was eight years ago. We are making hopeful gains," Bush said in a speech to the troops

He also said that he recognised that more troops were needed in the country and that he supported President-elect Barack Obama''s pledge to increase numbers. He said it was important to continue working with Pakistan so that pressure was kept on militants based along its border with Afghanistan.

"If Pakistan is a place from which people feel comfortable attacking infrastructure, citizens, troops, it''s going to make it difficult to succeed in Afghanistan. The more we can get Pakistan and Afghanistan to co-operate, the easier it will be to enforce that part of the border regions," he said.

Earlier, speaking on Air Force One en route to Afghanistan, Bush told reporters that his country''s goal there was similar to the one in Iraq - to let the new democracy develop its institutions so that it could survive on its own.

"The degree of difficulty is high. It''s hard. Nevertheless the mission is essential. We cannot. achieve our objective of removing the safe havens, kicking out the Taleban, and say: ''OK, now let''s leave''," he said. (ANI)