ISLAMABAD: Pakistan will hold historic general elections on May 11, a presidential spokesman said on Wednesday, after the government completed its first full term in the country's troubled history.

A caretaker administration will now manage the run-up to elections as the country struggles with Taliban violence, record sectarian unrest, chronic power cuts and a fragile economy.

The United States, a major aid donor despite tense relations with Pakistan in recent years, will be closely watching the elections in a country where the military shapes foreign policy with the help of the powerful intelligence agencies.

Nuclear-armed Pakistan is a key in ally in the U.S. fight against Islamist militancy and its cooperation is seen as vital in efforts to bring stability to neighbouring Afghanistan.

Pakistani Taliban militants are waging a violent campaign to topple the government and impose their austere brand of Islam. They recently withdrew a conditional ceasefire offer and threatened to attack the ruling party's election rallies.

Washington is hoping the elections will usher in stability so that Islamabad can help pacify Afghanistan as U.S.-led NATO troops prepare to leave by the end of 2014.

Pakistan's military has ruled the country for more than half of its 66-year history and its ties with civilian leaders are often strained.

Army chief General Ashfaq Kayani has vowed to keep the military out of politics and there are no signs the generals are backing any particular party for the polls.

Pakistanis have become frustrated with the ruling Pakistan People's Party (PPP) of President Asif Ali Zardari for its mismanagement of the fragile economy and inability to ease Islamist militancy and tackle poverty.

It could face strong competition from opposition leader Nawaz Sharif, who was toppled by a military coup in 1999, as well as cricketer-turned-politician Imran Khan.

Former military leader General Pervez Musharraf is expected to return from self-exile in Dubai on March 24 to take part in the election.