President Joyce Banda of Malawi has declared this week’s election to be “null and void”, throwing the nation into a new political crisis.

Speaking in the country’s capital Ilongwe on Saturday, Banda claimed there were “serious irregularities” with the poll.

Malawi’s leader alleged that people had voted multiple times, ballots had been tampered with, presiding officers had been arrested and that the computerised vote-counting system had been compromised.

“I am nullifying the elections, using the powers invested in me by the Malawi constitution,” she said.

Banda also ordered a fresh election within 90 days – but said she would not stand as a presidential candidate.

However, the head of the electoral authority challenged Banda, saying she did not have the power to annul an election, and that vote counting was continuing.

“As far as I know, the president doesn’t have any constitutional powers to nullify the election, only the electoral commission has the powers to do so,” the commission chairman Maxon Mbendera told the media.

A reporter reporting from Blantyre, said: “We still need to find out what the opposition parties think of the move … two of the frontrunners are due to arrive at the results centre soon,” she said.

Lameck Masina, a journalist based in Malawi, told the media that Banda’s move was surprising, but showed the leader had not performed as well as she had expected.

“The president has done this to show that she is still relevant to Malawians, although she is losing miserably at the polls she had a hope to win comprehensively.”

On Friday, the Malawi’s electoral commission said it had received 135 complaints of irregularities, which it was investigating before announcing the official results.

“We’re committed to a process that’s accurate and transparent. As far as we know, polling was free and fair in 99 percent of the centres and both local and international observers have commended the process,” said Mbendera.