MALE (Reuters) - The Maldives will hold a new presidential election on October 19, the election commission announced on Wednesday, after the Supreme Court annulled a September 7 poll citing voter fraud.

International election observers, including delegations from the Commonwealth, the United Nations, the European Union and India, had declared the September 7 election free and fair.

The tropical Indian Ocean resort archipelago will face a constitutional crisis if there is no president elected by November 11, according to a deadline set in 2008.

Former President Mohamed Nasheed, ousted from power 20 months ago in disputed circumstances amid a mutiny by police, won the first round on September 7 with 45.45 percent of the vote, but fell short of the 50 percent needed for outright victory.

The run-off, scheduled for September 28, had been expected to help end months of political turmoil triggered by the removal of Nasheed.

(Reporting by J.J. Robinson in Male; Writing by Shihar Aneez; Editing by Nick Macfie)