ISLAMABAD (Reuters) -- Pakistan's President Asif Ali Zardari has signed a regulation imposing Islamic Shari'a law in the Swat Valley in the northwest of the country, as part of a deal to end Taliban violence, state media reported.
Zardari signed the regulation late on April 13 after the National Assembly unanimously passed a resolution recommending he approve it, the APP news agency reported.
"Reportedly, as a result of the said peace agreement, the law and order situation is improving in Swat," the assembly said in recommending that Zardari sign the regulation.
Surging militant violence across Pakistan and the spread of Taliban influence through the northwest are reviving concerns about the stability of nuclear-armed Pakistan, an important U.S. ally vital to efforts to stabilize neighboring Afghanistan.
Authorities accepted an Islamist demand for Shari'a law in Swat in February to end more than a year of fighting but critics said appeasement would only embolden the militants.
Swat was one of Pakistan's main tourist destinations until 2007 when militants infiltrated into the North West Frontier Province valley from strongholds on the Afghan border to support a radical cleric.
Zardari, who has vowed to stand up to the spread of militancy, had faced pressure from conservatives and the main political party in the northwest, who said Shari'a law was the only way to bring peace to Swat.
The United States and other Pakistanis say deals with the Taliban create safe havens for them and their Al-Qaeda allies.
Some Pakistani Taliban fighters last week moved out of Swat, unopposed by the authorities, and into Buner district to the southeast.
Buner residents formed a militia to try to resist the militants and 13 people, including eight Taliban, three policemen and two villagers, were killed in clashes.
But the militants have prevailed and have begun imposing their rule in the mountain valley only 100 kilometers (60 miles) from the capital, police and residents said.