ISLAMABAD, Dec 4 (Reuters) - Pakistani Foreign Minister Khursheed Mehmood Kasuri will visit Kabul this week to discuss with Afghan authorities how to combat a growing insurgency in the ethnic Pashtun belt straddling their long, porous border. Pakistani President Pervez Musharraf and his Afghan counterpart, Hamid Kazai, agreed in September to call traditional tribal gatherings, or jirgas, on both sides of the border to win support against a resurgent Taliban. Relations between the uneasy neighbours have deteriorated sharply this year over Afghan complaints the Taliban get help on the Pakistani side of the border. Pakistan acknowledges the Taliban are getting some help from militant allies on its side of the border, but it says the Taliban are thriving because of mistakes being made in Afghanistan. "Basically, he will discuss how to bring about peace and calm in bordering areas of the two countries," Pakistani foreign ministry spokeswoman Tasnim Aslam told a weekly news conference, referring to Kasuri's Dec. 7-9 trip. "The focus would be how to activate traditional institutions to bring down violence and promote peace in the bordering areas," she said, referring to the proposed jirgas. Fighting in Afghanistan this year is the worst since U.S.-led forces ousted the Taliban's strict government in 2001. The violence has mainly been concentrated in Afghanistan's ethnic Pashtun south and east, in areas bordering Pakistan. More than 40,000 foreign troops are in Afghanistan, battling the Taliban and supporting Karzai's government. Pakistani security forces are also fighting militants in Pashtun tribal areas on Pakistan's side of the border. Hundreds of people have been killed over the past several years. The Pakistani government in September signed a peace deal with militants to halt fighting in North Waziristan, one of seven regions known as Federally Administered Tribal Areas, and to end militant infiltration into Afghanistan. It has been hoped the pact might serve as a model to end fighting elsewhere,even though the U.S. military said in the weeks after the deal was struck attacks had increased three-fold in some areas of Afghanistan opposite North Waziristan. Aslam said Kasuri would discuss Pakistan's strategy to use political and economic means in tandem with military tactics to combat the insurgency. "We would like to see peace in Afghanistan," she said. "It is our conviction that for that we require a comprehensive strategy which must have political reconciliation, massive economic reconstruction, apart from the military action that is already being taken."