Former cricketer Imran Khan has been sworn-in as the new prime minister of Pakistan, more than two decades after he entered politics.

He was elected prime minister in a vote at the country's National Assembly on Friday.

His PTI party won the most seats in July's elections and Khan has become PM with the help of small parties.

Correspondents say his priority will be to address a financial crisis, with the economy in need of a huge bailout.

On Saturday morning, Khan was tearful and smiled as he stumbled over some of the words of his oath, led by the country's President Mamnoon Hussain.

Members of the 1992 cricket World Cup winning team that Khan captained to victory watched the ceremony alongside senior PTI figures and military officials.

On Friday's vote, Khan was backed by 176 members. His opponent, Pakistan Muslim League-Nawaz (PML-N) president Shahbaz Sharif, received 96 votes.

In a speech to parliament, 65-year-old Khan reiterated his campaign promise to hold "corrupt" politicians to account, and to improve opportunities for young people.

"First of all, we will start strict accountability. I promise to my God that everyone who looted this country will be made accountable," he said.

"I did not climb on any dictator's shoulders; I reached this place after struggling for 22 years."

In the lead-up to the election, Khaan was seen as the favourite candidate of the military, which was accused of meddling to turn opinion against his rivals. (BBC)