KABUL, Afghanistan — Afghan President Hamid Karzai threatened Sunday to send Afghan troops across the border to fight militants in Pakistan, a forceful warning to insurgents and the Pakistani government that his country is fed up with cross-border attacks.

Karzai said Afghanistan has the right to self defense, and because militants cross over from Pakistan "to come and kill Afghan and kill coalition troops, it exactly gives us the right to do the same."

Speaking at a Sunday news conference, Karzai warned Pakistan-based Taliban leader Baitullah Mehsud that Afghan forces would target him on his home turf. Mehsud is suspected in last year's assassination of former Pakistani Prime Minister Benazir Bhutto.

"Baitullah Mehsud should know that we will go after him now and hit him in his house," Karzai said.

"And the other fellow, (Taliban leader) Mullah Omar of Pakistan should know the same," Karzai continued. "This is a two-way road in this case, and Afghans are good at the two-way road journey. We will complete the journey and we will get them and we will defeat them. We will avenge all that they have done to Afghanistan for the past so many years."

In Pakistan, Prime Minister Yousuf Raza Gilani said his country is a sovereign state that wants good relations with its neighbors. But he said the Afghan-Pakistan border is too long to prevent people from crossing, "even if Pakistan puts its entire army along the border."

"Neither do we interfere in anyone else's matters, nor will we allow anyone to interfere in our territorial limits and our affairs," Gilani told The Associated Press. "We want a stable Afghanistan. It is in our interest. How can we go to destabilize our brotherly country? Such kind of statements will not be taken well by the people of both countries."

NATO's International Security Assistance Force said it was not going to comment.

Karzai has long pleaded for Pakistan and international forces to confront militants in Pakistan, but has never before said he would send Afghan troops across the border.

His comments Sunday came days after a Taliban attack on the prison in Kandahar, an assault that freed almost 900 prisoners and which Karzai said underscored the challenges the country still faces.

U.S. officials have increased their warnings in recent weeks that the Afghan conflict will drag on for years unless militant safe havens in Pakistan are taken out. Military officials say counterinsurgency campaigns are extremely difficult to win when militants have safe areas where they can train, recruit and stockpile supplies.

Karzai said in recent fighting in the Garmser district of Helmand province — where hundreds of U.S. Marines have been battling insurgents the last two months — that most of the fighters came from Pakistan.

Karzai called Pakistan a "brother government" and "friend," but also urged it to "act against those elements that are making Pakistan and Afghanistan insecure." He said it was better for Afghan troops to be killed during offensive operations into Pakistan than in militant attacks in Afghanistan.

Karzai's comments also come as Pakistan is seeking peace deals with militants in its borders, including with Mehsud.

The deals have come under criticism from U.S. officials, who warn they will simply give militants time to regroup and intensify attacks inside Afghanistan. But Pakistan insists it's not negotiating with "terrorists," rather militants willing to lay down their arms.

Of particular concern is whether the deals will address militant activity inside Afghanistan.

Mehsud, who is based mainly in the South Waziristan tribal area, has said he would continue to send fighters to battle U.S. forces in Afghanistan even as he seeks peace with Pakistan.

U.S. and NATO commanders say that following the peace agreements this spring, attacks have risen in the eastern area of Afghanistan along the border.

Karzai said an assassination attempt against him in May and the Taliban's prison attack in Kandahar on Friday are "indicative of the weaknesses that we still have."

"Therefore it's all the more reason for us to work harder and keep building Afghan institutions and intelligence and to be a lot more alert and steadfast in our resolve in confronting terrorism," he said.


Associated Press writers Amir Shah in Kabul and Zarar Khan in Islamabad, Pakistan, contributed to this report.