Tourists have been cancelling hundreds of hotel bookings in Maldives every day since the imposition of a state of emergency last week, tour operators say, despite government assurances things are normal in the resort islands, far from the capital.

China, India, the United States and Britain issued travel warnings after President Abdulla Yameen imposed the emergency and arrested judges who had ordered him to free jailed opposition leaders.

"We have had about 50-60 room cancellations per day and the number is consistent since it started. This is the same for all of our properties in the country," said a spokesman for Paradise Island Resort-Villa Group which runs the 282-room hotel, a 20-minute ride by speedboat from Male where the turmoil is centred.

Tourism accounts for a third of Maldives' gross domestic product, measured at $3.5 billion in 2017. Ratings agency Moody's has said it would lower its 2018 growth forecast of 4.5 percent if tourists are deterred for a prolonged period.

Calls from Yameen's opponents for military intervention by India, the leading power in the region, have added to the uncertainty. The Muslim-majority nation of 400,000 people lies close to international shipping lines and has become another arena of contest between India and China.

China, which has built close ties to the Yameen government in its push for a network of friendly ports in the Indian Ocean under its "Belt and Road" initiative, has cautioned against foreign interference. But that hasn't stopped it from issuing a travel warning to its citizens, who make up a fifth of the tourist traffic.

Almost 1.4 million tourists from across the world visited the Maldives in 2017, according to government statistics.

Trouble began on the idyllic islands, famed for white-sand beaches and crystal clear diving spots in its turquoise waters, when the Supreme Court quashed terrorism and graft convictions of nine opposition figures and ordered they be freed. Among them was the exiled former president, Mohamed Nasheed.

Yameen rejected the ruling and declared an emergency for 15 days. He also ordered the arrest of two of the court's five judges, several opposition members and his 80-year-old half-brother, Maumoon Abdul Gayoom, who had ruled the Maldives for 30 years. They were all plotting a coup against him, Yameen said. The remaining judges have since nullified the court's ruling and the government sent envoys to China, Saudi Arabia and Pakistan seeking support from "friendly" nations and to reassure them the islands were safe for international travel.