Beijing's foreign ministry said it was paying close attention to events in the Maldives and had asked the government in Male to protect Chinese interests there

A Chinese naval combat force that entered the Indian Ocean for the first time in four years may have helped deter an Indian intervention in the Maldives after its pro-China president imposed a state of emergency, according to military and diplomatic sources and analysts.

India has traditionally been the biggest player in the tiny island chain 400 km (250 miles) to its south, and faced calls from Maldives' opposition leaders last month to use force against President Abdulla Yameen to restore democracy.

After the state of emergency was declared India - which sent troops to foil a coup in the Maldives three decades ago - moved aircraft and ships to its southern bases and put special forces on standby, two military sources in New Delhi said.

But in the end, Prime Minister Narendra Modi held off from hard action, unwilling to entangle the military in a foreign country of 400,000 people, the sources said.

Beijing's signals it would not look kindly on any foreign involvement in the Maldives - where it is investing millions of dollars as part of its Belt and Road Initiative - backed up by its naval presence in the eastern Indian Ocean, may also have weighed against an intervention, security analysts said.

China's defence ministry said the ships carried out routine exercises. "These drills were normal exercises for this year and not aimed at any third party," the ministry said in a statement to Reuters, when asked whether the manoeuvres were linked to the crisis in Maldives. It did not elaborate.

Beijing's foreign ministry said it was paying close attention to events in the Maldives and had asked the government in Male to protect Chinese interests there.

India's defence ministry did not respond to a request for comment. A naval official confirmed the Chinese ships entered the Indian Ocean, but said they were thousands of miles away from the Maldives.

"The Indian navy has a robust maritime domain awareness and we have a clear picture of the happenings in the Indian Ocean Region," the official said.

Details of the deployments by India and China as well as diplomatic messages from Beijing that have not previously been reported, show how the Asian giants flexed military muscles as the crisis in the strategically located archipelago unfolded.

Both militaries have since backed off and last week Vijay Gokhale, India's top diplomat, made an unscheduled visit to Beijing where the two sides discussed ways to address their "differences on the basis of mutual respect and sensitivity to each other's concerns, interests and aspirations," the Indian foreign ministry said. It did not give more details.

Liu Zongyi, a South Asia expert at the Shanghai Institutes for International Studies, told the People's Daily in January that Yameen's tilt towards China had caused unhappiness in New Delhi.

India had been infuriated with the signing of a free trade deal with China last December, he said, adding: "The political unrest in the Maldives in actual fact is a power struggle with international factors."

At the end of January, a Chinese navy "surface action group", which included an amphibious Type 071 vessel for troops to make a marine landing, quietly crossed into the Indian Ocean through Indonesia's Sunda Straits.

It was the first time such a force entered the area since an exercise by a similar group in 2014 in the eastern Indian Ocean that raised concern in India about Chinese motives behind conducting amphibious drills.

Thousands of miles away in the Maldives, Yameen, long criticised for running his Muslim majority nation with an iron fist, rejected a surprise Supreme Court decision on Feb. 1 to free political dissidents.

Instead, the Maldives' leader threw the judges too into prison and imposed a state of emergency, saying he was acting to thwart a coup.

Beijing said events in the Maldives were an internal matter and the international community should play "a constructive role" and avoid "further complicating the situation". Meanwhile, the People's Liberation Army posted photos of the warships, whose number had by then swelled to 11, taking part in rescue training exercises, according to Chinese state media.

Some analysts saw a carefully calibrated message from China.

"These are 'grey zone' tactics, you don't raise the level of provocation to a level that the adversary finds a reason to react or retaliate, but you send the message home," said Abhijit Singh, a former Indian naval officer, at the New Delhi-based Observer Research Foundation.

"The message to India was: 'if you come too close to the Maldives, we are not too far away'."

China, whose navy is now four times bigger than India's, is increasingly asserting itself in the Indian Ocean. It has built a network of friendly ports, its so-call "String of Pearls", around shipping lanes through which more than three-quarters of its oil moves.

Soon after the emergency was declared in the Maldives, India's military moved C-130 Super Hercules and C-17 Globemaster transport planes from near Delhi to its Yelahanka air force base near the southern city of Bengaluru, and ordered paratroops to be on stand-by, the two Indian military source said.

Warships were also put on readiness at the southern naval command in Kochi, they said. A government official dealing with security issues said moving planes and ships was standard operating procedure for the military.

A few days later the Indian navy launched "large-scale operational exercises" in the western Indian Ocean involving 40 warships including an aircraft carrier. The naval official said these were pre-planned.

Yameen was unfazed, and on Feb. 20 extended the emergency by another 30 days despite international calls not to do so.

A source close to Chinese diplomats in Colombo said that Beijing had told its missions in the region that China stood ready to help Yameen if India tried to unseat him. The source was not clear whether that included military help.

A diplomat at the Maldives' embassy in Colombo said Beijing had given the same assurance of support to the Yameen government. A second diplomat said China had been dragged into the political crisis by the Maldivian opposition, which accused Beijing of grabbing some of its islands.

Throughout the crisis, the Maldivian government was in continuous contact with the Chinese embassy in Male and China was informed about Yameen's every move, including the state of emergency well, in advance, the first diplomat said.

"The Chinese interest is purely commercial," Maldives' minister of fisheries and agriculture Mohamed Shainee said. "They have invested a lot and they have to protect their investments."