Malawi's former President Peter Mutharika has been declared the winner of last week's elections, in a huge comeback for the 85-year-old.

Official results show that he won 57% of the vote, compared to the 33% of President Lazarus Chakwera, 70.

Chakwera, a pastor before entering politics, conceded defeat ahead of the final result being declared, phoning Mutharika to congratulate him on his "historic win".

Mutharika, a former professor of law, served as president from 2014 to 2020, when he lost to Chakwera by a wide margin.

He inherits an economy that is in deep crisis, with a severe shortage of fuel and foreign currency in the poor southern African state.

The official inflation rate is close to 30%, with a frozen chicken in a supermarket in the capital, Lilongwe, costing about $20 (£15), in a nation where most people live on $2 a day or less.

Mutharika is due to address the nation later on Thursday.

The election commission said it took the full eight days it was allowed to announce the result because it wanted to check everything carefully and address the complaints first.

The 2019 election, also won by Mutharika, was annulled by the country's highest court, which found there had been widespread irregularities, including the use of correction fluid to alter results.

Chakwera won the rerun by a huge margin the following year.

This was the pair's fourth electoral duel.

Mutharika's older brother Bingu also served as president and died in office in 2012.

In his concession speech, Chakwera said that even though he had concerns about "irregularities" and "anomalies", he was accepting the outcome out of respect for the majority of Malawians' "collective will to have a change of government".

"The anomalies do not necessarily mean that the election result projecting Professor Mutharika as the winner is not credible or a reflection of the will of the people," he said.

His speech sparked celebrations among Mutharika's supporters in Lilongwe, with hundreds singing and dancing on the streets.

Motorists could be heard beeping their horns and playing loud music, while pedestrians danced, sang and chanted "adadi", which means father in the local Chichewa language.

Appearing keen to see the back of Chakwera, a group of men in Lilongwe ripped down a poster of the outgoing president's head and began stamping on it.

"Achoke!" they chanted, which means "he must go" in Chichewa.

Mutharika's supporters later gathered to celebrate at the local Civo stadium where Chakwera held his final campaign rally. The celebrations continued overnight.

This result can be seen more as a rejection of Chakwera than a victory for Mutharika.

Under President Chakwera, Malawi's list of problems just grew too long.

Corruption on a grand scale, a weak economy, high living costs, frequent power cuts and a shortage of foreign currency pushed Malawians to look elsewhere for leadership.

Although these same problems existed during Mutharika's tenure, they worsened under Chakwera.

Chakwera's allies blamed the crisis on factors out of his control, including drought and other natural disasters, the Covid pandemic and the war in Ukraine.

However, Mutharika's campaign mantra - "a return to proven leadership" - resonated with Malawian voters.

But now Mutharika will have to show that he can once again tackle inflation, as he did in his first term.

Mutharika was rarely seen in public during the campaign, in contrast to Chakwera who held numerous rallies across Malawi.

As a result, speculation about Mutharika's health is rife and there are questions about whether he has the stamina to lead Malawi again at the age of 85.

The swearing-in ceremony must be organised between seven and 30 days after the announcement of the result.