Maldives President Abdulla Yameen's administration today said legal conflicts made it difficult to comply with a Supreme Court order to free jailed opposition leaders, deepening a political crisis in the Indian Ocean island nation.

Also read: Maldives political crisis deepens

Yameen, who has run the country with an iron hand since 2013, is facing mounting pressure at home and from the United States and India to release former president Mohamed Nasheed from a 13-year jail sentence, and free eight other political opponents from prison.

The Maldives, home to 400,000 people and best known as a tropical paradise for tourists, has experienced political unrest since Nasheed, the island's first democratically-elected leader, was forced to quit amid a mutiny by police in 2012.

The following year, Yameen then defeated him in an election that Nasheed maintains was rigged. Subsequently, imprisoned on terrorism charges, Nasheed was allowed to go to Britain for medical treatment in January 2016, and has been living in exile since, though he is currently in Sri Lanka.

In its ruling last Thursday, the Supreme Court said it found that prosecutors and judges had been influenced "to conduct politically motivated investigations" into the allegations levelled at Nasheed, former vice president Ahmed Adeeb and the other opposition leaders.

The court also ordered fresh investigations and trials to be held.

The ruling has energised an opposition that hopes Nasheed will be allowed to return home to run against Yameen in a presidential election due in October.

Anticipating a possible escalation by the Supreme Court, Attorney General Mohamed Anil has warned that the government will resist any attempt to impeach Yameen for non-compliance with the order.

On Monday, a minister quit in protest at the government's defiance of the Supreme Court.

"It is not possible for my conscience to accept the lack of answers to the way the government is dealing with the orders of the highest court on state institutions," Hussain Rasheed, the state health minister, said in his resignation letter.

Speaking to state run TV Maldives, Legal Affairs Minister Azima Shakoor sought to justify the government's stance.

"There are many legal challenges...and these challenges made it difficult to enforce the ruling. The criminal justice system will be compromised if the ruling's orders to free the prisoners is enforced," she said, without elaborating.

Since Thursday's ruling, Yameen has fired two police chiefs who tried to implement the court ruling and a politically neutral secretary general of parliament, who was also to implement the ruling, has resigned.

Police has started investigations into Supreme Court judges and officials since the ruling, and have said that they plan to question former president Maumoon Abdul Gayoom, who is now in the opposition, in a separate case.

Gayoom, who is a half-brother of Yameen, said unidentified armed men had tried to intimidate him overnight.

"A band of thugs armed with knives drove by my residence several times after midnight last night shouting abuse at the top of their voice. I wonder who sent these unruly thugs?" Gayoom said in his Twitter feed.

The country's combined opposition urged foreign powers to put pressure on Yameen to yield to the rule of law.

"We..request the international community to consider and implement all necessary measures - including diplomatic, economic, and legal - to defend democracy, rule of law, and human rights in Maldives at this critical juncture," the joint opposition said in a statement.

The political drama in the Maldives, which is made up of 26 coral atolls and 1,192 individual islands, is being played out in the tiny, but densely populated capital of Male.

But China on Monday advised its citizens to avoid visiting the Maldives until political tensions subside on the Indian Ocean archipelago.