New Delhi: Prime Minister Narendra Modi on Sunday hailed the Maldives as a “valued partner" of India in the Indian Ocean region on the occasion of its 50th independence day, saying ties between the neighbours are based on a “strong foundation."

J.P. Nadda, a senior minister in the Modi-led government, represented India at the official celebrations in Male on Sunday.

The gestures, however, mask a strain in ties between South Asia’s biggest power and the small, mainly Sunni Muslim nation of around 400,000 people and more than 1,200 atolls that sits astride some of the busiest sea lanes in the world.

The Maldives has been wracked by political instability since the exit of president Mohammed Nasheed—seen as close to India—in 2012. He was succeeded by then vice-president Mohammed Waheed.

India recognised Waheed almost immediately after he succeeded Nasheed and promised help to his administration during a visit to India in May 2012. But New Delhi was in for a rude shock when Waheed’s government cancelled a $500 million contract awarded to a joint venture between India’s GMR Group and Malaysia Airport Holdings Bhd to build an airport in Male.

Elections in the Maldives in 2013 brought to power Abdulla Yameen Abdul Gayoom, half-brother of former president Maumoon Abdul Gayoom, who preceded Nasheed as president and administered the atoll nation for three decades. India welcomed Yameen during a state visit in December 2013, just a month after he took office. Yameen was also among the leaders invited for Modi’s swearing-in ceremony in May last year.

But Yameen’s perceived closeness to India’s rivals China and Pakistan seemed to have cooled the early warmth in ties.

“We have no objections over Maldives or any country forging good relations with another country. But what we expect is sensitivity to our concerns," said a person familiar with the developments when asked what had caused the souring of ties.

According to former foreign secretary Kanwal Sibal, “India has been unable to isolate itself from the domestic quarrels in the Maldives. There seems to be no clarity on which side India should back." He pointed to some instances where India had come to the defence of Nasheed, moves viewed as antagonistic by those in power.

Adding to India’s woes is China’s looming presence. “The Maldives can cushion itself against any sort of Indian pressure thanks to the Chinese. The Maldives’ geopolitical situation in the Indian Ocean makes it critical for Chinese maritime trade plans," said Sibal.

India’s concern stems from the rising Chinese naval profile in the region. Projecting India’s primacy was seen as one of Modi’s major aims during a March visit to Seychelles, Mauritius and Sri Lanka. Modi was to visit Maldives but the speedy trial and conviction of Nasheed on charges of terrorism kept him away. According to two people familiar with the developments, India decided against the visit as it would have been seen as an endorsement of the Maldivian government against Nasheed.

According to one of the people cited above, New Delhi has always stood by the Maldives in its times of crises—the most recent example being India airlifting tonnes of drinking water to the Maldives after a fire in a desalination plant in December cut off water supplies to some 100,000 residents in Male. What riled New Delhi after that were some articles in local newspapers that accused India of triggering the crisis, something that Male did nothing to dispel.