* Maldives set for showdown over run-off election
* Election commission seeks to override Supreme Court
* Police say they back court decision to delay poll
By J.J Robinson
MALE, Sept 26 (Reuters) - The Maldives will go ahead with a presidential election run-off on Sept. 28, election commissioner Fuwad Thowfeek said on Thursday, despite a decision by the Supreme Court to postpone the second round following a complaint of vote rigging.
Thowfeek's comments followed mounting international pressure on the government to push ahead with a run-off, amid hopes that the vote could help end months of political turmoil in the Indian Ocean archipelago.
Thowfeek said the Supreme Court had no right to override the constitution, which stipulates that a run-off vote must be held within three weeks of the first round.
"We don't believe any organisation or institution can overshadow the constitution. So we are working toward the constitution," he told Reuters, amid calls for his arrest by some politicians for contempt of court.
"I don't care about punishment from the Supreme Court. They should uphold the constitution."
The first round of voting, on Sept. 7, was won by ex-president Mohamed Nasheed, whose removal from power 20 months ago ignited months of unrest.
"We welcome the Elections Commission decision. I ask all parties to respect this decision," tweeted Nasheed, forced from office in February 2012 when mutinying police and soldiers armed opposition demonstrators and gave him an ultimatum.
He secured 45.45 percent in the first round, short of the 50 percent needed for outright victory, and his party promptly announced mass protests against the postponement.
Soon after Thowfeek's announcement, police set up barricades near the election commission's headquarters, where the five-member committee held its meeting to decide on the run-off.
A Reuters reporter saw police taking away at least three people in the crowd gathered outside the building in handcuffs.
Thousands of Nasheed's supporters gathered near the country's tsunami monument in Male, the capital of the chain of islands that is home to a series of luxury hotels popular with tourists from around the world.
Abdulla Yameen, half-brother of long-time ruler Maumoon Abdul Gayoom was placed second in the presidential poll, just ahead of Gasim Ibrahim, a tourism and media tycoon who was finance minister under Gayoom.
It was Gasim's Jumhoory Party (JP) that asked the Supreme Court to annul the first round result, alleging voting irregularities, a move that Nasheed's Maldivian Democratic Party(MDP) dismissed as unconstitutional.
Yameen's vice presidential candidate Mohamed Jameel Ahmed said the election commission did not have the mandate to hold the election against the will of the Supreme Court.
"Our view is very clear: the election cannot go ahead. We will not allow it, no one in the country will allow it," he said.
Nasheed's successor President Mohamed Waheed, under pressure to hold the run-off as scheduled, asked the international community to refrain from making statements on the election.
"Irresponsible statements by foreign governments and international organisations would not be helpful in consolidating democracy in the country," he said.
The Interior Ministry said it would do "everything necessary to ensure the safety and security of the beloved Maldivian people", and asked the public to respect the Supreme Court ruling.
Whether the second round will be held on Sept. 28 remains to be seen. Although the MDP controls parliament, the police have already informed the election commission that they will abide by the Supreme Court ruling.
Nasheed served for three years as the Maldives' first democratically elected president, and protests by his supporters were met with a heavy police crackdown that tarnished the Maldives' image as a tranquil holiday paradise.
Political analysts and human rights campaigners say the islands have been in political and economic limbo ever since.
Critical challenges facing the next president include a rise in Islamist ideology, human rights abuses and a lack of investor confidence after the government cancelled the Maldives' biggest foreign investment project with India's GMR Infrastructure .