Many doubt that any barricade will curb the Taleban's activities

Few people expect Pakistan's proposal to control militant infiltration into Afghanistan by fencing and mining their joint border to be a workable solution.

But many fear it may aggravate the situation in Pakistan's north-western tribal areas, and increase friction with Afghanistan.

That was evident at a joint press conference held by the Afghan President, Hamid Karzai, and the Pakistani Prime Minister, Shaukat Aziz, in Kabul on Thursday.

Mr Aziz insisted that the border proposals would curb the infiltration of pro-Taleban militants into Afghanistan.

But Mr Karzai was of the opinion that this will divide the tribes.

The decision to selectively fence and mine the border, including high-traffic zones, was formally announced by Pakistan's Foreign Secretary Riaz Mohammad Khan on 26 December.

It came weeks after Mr Karzai's remarks that Pakistan was trying to "enslave the Afghans".

The proposal itself is not new.

Pakistan says a fence will help stop militants crossing the border

Pakistani President Pervez Musharraf first introduced the idea in September 2005, sparking a debate in both countries.

It was unanimously opposed by different political circles in Afghanistan. The reaction in Pakistan was mixed.

Initially, Pakistan said it would seek US support as well as funding for the project, but that did not materialise, probably due to opposition from Kabul.

Now that Pakistan has announced its intention to go ahead with the project, the opposition within Pakistan has grown stronger.

Nationalist groups in North West Frontier Province and Balochistan have termed the decision as "detrimental to the social and economic interests of the ethnic Pashtun tribes".

The idea is also being opposed by the larger political parties, including the six-party religious alliance, the MMA.

While such opposition is partly couched in domestic politics, much of it draws on the conditions prevailing in the tribal areas.

All seven tribal districts along the Afghan border are inhabited by tribes that live on both sides of the border.

Not only are their lands and businesses interconnected, they also share the same social mechanism - the jirga or tribal council - whereby each tribe runs its own affairs and adjudicates its own disputes.

Fencing the border, especially areas of high intra-tribal interaction, would adversely affect the economic and public life of the people.

The United Nations fears that mining the border would also increase risk to human life in an area which is already littered with ordinance from nearly 30 years of war in Afghanistan.