President Bush says foreign troops that support the government in Afghanistan are changing their tactics to confront a renewed insurgency by Taleban militia. Mr. Bush met with Afghan President Hamid Karzai in the Oval Office.

President Bush and Afghanistan's President Hamid Karzai hold a joint press conference, September 26, 2006

President Bush says Taleban and al-Qaida fighters are trying to bring down President Karzai's government because they realize that democracy in Afghanistan will make it more difficult for them to use the country to launch terrorist attacks elsewhere.

"In recent months, the Taleban and other extremists have tried to regain control, mostly in the south of Afghanistan. And so we have adjusted tactics," the president said. "And we are on the offense, to meet the threat and to defeat the threat."

President Bush said members of the NATO alliance fighting in Afghanistan will not leave until that enemy is defeated. Speaking to reporters following White House talks with President Karzai, Mr. Bush said many Afghan forces are fighting bravely for the future of their country.

He expressed his regret about the assassination of the provincial director of Afghanistan's Ministry of Women's Affairs, Safia Ama Jan. Mr. Bush says her killing shows the nature of an enemy he says has no conscience.

"Their objective is to create fear, to create enough violence so we withdraw and let them have their way, and that is unacceptable," he said. "It is unacceptable behavior for the free world and the civilized world to accept, Mr. President."

President Bush says fighting in Afghanistan is part of a global struggle against terrorism, a battle in which he says every victory enhances security for free people everywhere.

The president's meeting with President Karzai comes just days after talks with Pakistani President Pervez Musharraf. The two neighbors and key U.S allies have had their differences. They have accused each other of not doing enough to stop violence along the remote border region where neither central government has much control.

As part of an effort to soothe some of those differences, Mr. Bush will bring President Karzai and President Musharraf together for dinner Wednesday at the White House.