Eleven Chinese warships reportedly sailed into the East Indian Ocean this month, amid a constitutional crisis and state of emergency in the Maldives.

Key points: Maldives are in debt to China for aid and infrastructure work

Maldives are in debt to China for aid and infrastructure work China and India are in strong competition over the South China Sea

China and India are in strong competition over the South China Sea Pacific countries now concerned China could make similar power play in region

A fleet of destroyers and at least one frigate, a 30,000-tonne amphibious transport dock and three support tankers entered the Indian Ocean, news portal Sina.com.cn said, without linking the deployment to the crisis in the Maldives or giving a reason.

"If you look at warships and other equipment, the gap between the Indian and Chinese navy is not large," Sina.com.cn said.

It did not say when the fleet was deployed or for how long.

India and China's competition for influence in the Maldives became evident after President Abdulla Yameen signed up to Beijing's One Belt, One Road initiative to build trade and transport links across Asia and beyond.

India, which has had longstanding political and security ties to the islands about 400 kilometres away, has sought to push back against China's expanding presence in the overwhelmingly Muslim country of 400,000 people.

Maldivian opposition leaders have urged New Delhi to intervene in the crisis.

China's Ministry of Defence did not respond to requests for comment.

On Friday, the People's Liberation Army posted photos and a story on rescue training exercises taking place in the East Indian Ocean on its official Weibo account.

Earlier this month, China advised Chinese citizens to avoid visiting the Maldives, famous for its luxury hotels, scuba-diving resorts and limpid tropical seas, until political tensions subside.

President Yameen imposed a 15-day state of emergency on February 5 to annul a Supreme Court ruling that quashed convictions against nine opposition leaders and ordered his government to free those held in prison.

He sought parliamentary approval to extend the emergency for 30 days, with parliament approving the extension despite international calls to lift the emergency and restore normalcy.

'China aid is not simply aid, they're loans'

Protesters have been demanding that the Maldives Government obeys a court order to free opposition leaders from prison. ( AP: Mohamed Sharuhaan )

China has been striking deals with countries in Asia and the Pacific in line with its One Belt, One Road initiative to improve imports of key commodities, upgrade infrastructure and trade routes in the region and boost its diplomatic clout.

Beijing's decision to send warships into the Maldives region during their current crisis has raised concerns that China could make a similar power play in the Pacific region.

Fiji's former department of foreign affairs secretary Robin Nair told the ABC's Pacific Beat program that the situation shows China's growing influence in the Pacific could leave some nations in difficult debt situations.

"I think there is general concern that the Pacific is opening itself to the same dangers in the sense that it is going into great debt," Mr Nair said.

"We know that in the Maldives, China has been involved in developing their infrastructure and the Maldives are in heavy debt to China at almost $2 billion, which is unrepayable for a small country like that."

Mr Nair said that while countries like Australia and New Zealand provide a lot of on the ground support and disaster relief, Chinese aid money comes with a catch.

"Chinese aid is not simply aid, but they are loans, concessional loans," Mr Nair said

"China is much more calculated in the way it reacts. It reacted just by sending some money into Fiji after the cyclone [Winston]."

Mr Nair said the public was wary of China's influence in the region.

"I think that the influence of China on the Pacific, it might have some influence on the leaders and some Governments but not on the people," he said.

"The people also know and are very much conscious of the debt burden that the countries are undertaking, and they are also most worried about the quality of the management and the quality of the work in those aids projects."

China has drawn criticism in the West for its perceived military build–up of the neighbouring South China Sea, where it has built and expanded islands and reefs.

China claims most of the sea where neighbours Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims.

ABC/Wires