A Pakistani court has ordered the arrest of former president Pervez Musharraf.

He is charged in connection to his showdown with the judiciary in 2007 when he was still in power, television channels and one of his aides said.

The former army chief returned to Pakistan last month after nearly four years of self-imposed exile to contest a 11 May general election.

Election officials had barred Mr Musharraf from running for the National Assembly earlier this week, effectively derailing his attempts to regain a place in politics by standing at the polls.

Former prime minister Nawaz Sharif, the man Mr Musharraf ousted in a coup in 1999, is seen as the frontrunner to win the election.

"Islamabad High Court has cancelled Musharraf's bail and ordered his arrest in the judges' detention case today," a spokesman for Mr Musharraf's All Pakistan Muslim League party said.

Mr Musharraf was ordered to be detained in connection with allegations that he committed treason when he sacked senior judges and declared emergency rule as he struggled to hold on to power.

Critics said he acted unconstitutionally.

Police made no immediate move to enforce the arrest order and Mr Musharraf left the court flanked by his personal bodyguards.