ANTANANARIVO, Feb 3 The Madagascar government on Tuesday sacked the capital city's mayor, Andry Rajoelina, who said he would challenge the decision, escalating a power struggle with the island's president.

Rajoelina, who has embarked on a drive to oust President Marc Ravalomanana, was replaced as Antananarivo mayor by a special administration, top interior ministry official Edmond Rakotomavo said.

“There was a decree issued by the interior ministry replacing the capital's leadership with a special delegation,” Rakotomavo said. “We wanted to notify the mayor but he was not there.” But Rajoelina said he planned a rally of his supporters in the capital to protest the decision.“Tomorrow we will prove that we are all united to challenge the decision of the ministry,” he said.

“Tomorrow, the people who voted for Andry Rajoelina will gather before the city hall,” he told reporters.

“Antananarivo will not accept this decision. There is no valid reason to sack me,” he said, adding “I don't fear being arrested.” The 34-year-old mayor has emerged as the undisputed leader of Madagascar's opposition, building support on widespread popular grievances over poverty and violations of civil liberties.

He was replaced by a three-man team headed by Guy Randrianarisoa who has already served as Antananarivo municipality secretary general as well as the deposed mayor's special adviser during his first five months in office.

“I do not play politics, I am not TIM, I am not anything. I was appointed only to manage,” Randrianarisoa said.

TIM, or “I love Madagascar,” is Ravalomanana's ruling party.

“I am here to ensure Antananarivo residents come together again and make our town shine and not what we witnessed last week.” Protests hit the capital city and other towns last week, leading to riots that left at least 68 dead.

The demonstrations were called by Rajoelina who has branded the president's regime a dictatorship and sought his removal. On Monday he petitioned the Constitutional Court to oust Ravalomanana.

But only the senate and parliament, where Ravalomanana's party holds the majority, can intitiate an impeachment process.

A Madagascar watcher said Rejoelina's dismissal is an indication that Ravalomanana is “re-taking control of affairs and that he feels capable of doing that.” Rajoelina, who proclaimed himself in charge of Madagascar's affairs over the weekend, announced on Tuesday he would unveil a transition government.

“I will announce the new government on Saturday,” the opposition leader told a crowd of several thousand supporters gathered in the island's capital.

The latest protests called by Rajoelina drew dwindling numbers but the opposition leader announced that one of the island's most popular singers would appear in a rally on Saturday.

The new Antananarivo city chief, with two deputies, said he did not know the duration of their mandate nor the exact reasons why the changes were made, but said there were “shortcomings in the running of the municipality, such as waste management.” Ravalomanana and his younger rival have been at odds since the mayor's election in 2007.

But their tug-of-war worsened in December when authorities shut Rajoelina's TV network for airing an interview with former president Didier Ratsiraka.

UN Secretary General Ban Ki-moon said on Monday he was particularly concerned about the unrest in the the Indian Ocean island, which has suffered political turmoil in the past.

Other states, including former colonial power France have appealed for calm and a negotiated agreement between the rivals. —AFP