ISLAMABAD: Pakistani clerics threatened Tuesday to boycott a peace conference in Afghanistan after a dispute over whether to invite the Taliban, another sign of how hard it will be for the two states to cooperate on a deal to end the 11-year-old Afghan war.

The dispute followed talks between Pakistani and Afghan clerics in Islamabad that ended Monday. The visiting Afghan delegation, which sought to play down the disagreement, was in town on a seemingly simple mission to finalise plans for a conference of religious scholars in Kabul next month meant to denounce suicide attacks and other forms of violence in the name of Islam.

Kabul and Islamabad announced the plan for the conference in November as a sign of improving relations. But the latest talks seemed to do more to highlight longstanding disputes, especially over the Taliban.

Pakistan helped the Taliban seize control of Afghanistan in the 1990s. Afghan officials have accused Pakistan of maintaining ties to the group _ an allegation denied by Islamabad.

Many analysts agree that the Pakistani military continues to view the Taliban as an important counterweight to Afghan President Hamid Karzai's government, which is seen as too close to Pakistan's archenemy, India.

Tahir Mehmood Ashrafi, head of the All Pakistan Ulema Council and also the chief of Pakistan's five-member delegation, accused the visiting Afghan clerics of trying to use the upcoming conference to denounce the Taliban and elicit support for the Afghan government. He insisted the Taliban be invited to the event to advance the peace process.

''I want to make it clear that there is consensus among almost all the Islamic scholars that this conference of clerics will be worthless if the Taliban are not invited to participate,'' Ashrafi told The Associated Press.

He accused the Afghan clerics of being too close to the government and threatened Pakistani religious leaders would boycott the upcoming meeting because of differences between the two sides. Ashrafi is seen as close to Pakistan's security establishment.

A member of the Afghan delegation, Aminullah Muzafery, painted the meeting in a more positive light and sought to downplay Ashrafi's comments, although he never mentioned him by name.

''There was a person who tried to sabotage the process,'' Muzafery said at a press conference Tuesday in Kabul. ''The Pakistani side was also not happy with what he was saying and they didn't want him in the meeting. When he was told not to attend, he said things to the media that were his own opinion.''

Ashrafi, whose group represents thousands of Pakistani clerics, disputed Muzafery's comments. But another member of the Pakistani delegation, Qari Roohullah Madni, took a more moderate line and said it was up to the Afghans to decide who to invite to the conference.

The two sides agreed the conference would be held in Kabul in March after another planning meeting on Feb 21 in the Afghan capital, according to a press release distributed by the Afghans.

The conference would include 250 clerics each from Pakistan and Afghanistan and 500 clerics from other Muslim nations. It will focus on peace and security in Pakistan and Afghanistan, as well as in other Muslim countries.

''The conference will not be in support of or against anyone and/or any group,'' said the press release.

Muzafery made clear to the AP that the Afghans could not invite the Taliban to the meeting. He said he asked the Pakistanis whether they would invite the head of the Pakistani Taliban if the conference was in Islamabad.

The group is at war with the Pakistani government. ''They said that would not be possible, so we told them that if that is not possible, how would it be possible for us to invite anyone from the (Afghan) Taliban to our conference in Kabul?'' said Muzafery.

The Afghan and Pakistani Taliban are allies but have focused their fight on different enemies. The Afghan Taliban have carried out attacks against US-led forces in Afghanistan, while the Pakistani Taliban have focused on fighting in Pakistan.

Despite the clash between the clerics, there has been some progress in improving relations between the two countries in recent months.

Pakistan has released over two dozen Taliban prisoners in an attempt to facilitate the stuttering peace process with the militant group _ complying, at least partially, with a longstanding demand by Kabul.

But the prisoner release has also caused friction with Kabul _ and Washington _ which are both frustrated that Pakistan is not monitoring the whereabouts and activities of the former inmates. They are worried the prisoners may simply rejoin the insurgency.