The government of the Maldives will resist any attempt by the Supreme Court to impeach President Abdulla Yameen for disobeying its order last week to release jailed opposition leaders, the attorney general said on Sunday.

Mohamed Anil said the government had received information that the Supreme Court was preparing to fire Yameen, but such a move would be illegal and the police and army had been instructed not to carry out such an order.

"We have received information that things might happen that will lead to a national security crisis," Anil told a news conference in the capital, Male, at which the head of the armed forces and new police chief also appeared.

"The information says the Supreme Court might issue a ruling to impeach or remove the president from power."

Yameen has fired two police chiefs since Thursday, when the Supreme Court threw out terrorism convictions against former president Mohamed Nasheed and eight other opposition figures. Police had indicated they would enforce the ruling.

Some of the jailed opposition leaders have said they have evidence of corruption by Yameen, who has denied all such allegations.

The court also ordered 12 members of parliament who had been stripped of their seats to be restored to the body.

The 12 had quit Yameen's ruling party last year, and allowing them to return to the legislature would deprive him of a majority.

The politically neutral secretary general of parliament, Ahmed Mohamed, had said he would abide by the Supreme Court's order to reinstate the 12 lawmakers but he unexpectedly resigned on Sunday, citing personal reasons.

Yameen, in power since 2013 and facing elections in October, is under international pressure to heed the court decision, while hundreds of protesters have taken to the country's streets to demand compliance with the order.

In a statement late on Sunday, the Supreme Court said there should be "no legal barrier" preventing the enforcement of its ruling but made no mention of whether it was seeking to impeach the president.

Earlier in the day more than 100 riot police stood guard outside government offices in Male, including parliament, as well as at Republic Square, a site of protests by opposition activists, although the streets were quiet.

The Maldives National Defence Force said in a statement that it would work to stop activities that "openly threaten the security and safety of the Maldives" or which sought to spread "false and unfounded rumours" about the government.

The combined opposition said in a statement that it feared a military takeover of the Indian Ocean archipelago to preserve Yameen's grip on power. It said the attorney general's "highly irregular statement supported by the two chiefs of the security forces" was "tantamount to the effective sidelining of the judiciary and in direct contravention of the constitution".

"Maldivians are fearful that President Yameen is about to order a full military takeover of the country, in an attempt to ensure he is not removed from office," the statement added.

Nasheed, the country's first democratically elected leader, lives in exile in Britain but is currently in Sri Lanka. He is fighting for the right to contest the presidential poll after losing power to Yameen in a 2013 election which Nasheed's supporters said was rigged.

The Maldives, an Indian Ocean island chain of around 400,000 people known to outsiders mainly as a tropical paradise for the tourists that provide most of its foreign exchange income, has experienced political unrest since Nasheed stepped down in 2012.

Facing the biggest challenge of his presidency, Yameen has stopped short of saying he will not obey the court order. He told a party meeting on Saturday, "he did not expect the Supreme Court ruling at all".

Critics of the government continued to face pressure, however.

On Sunday, police raided the home of Hassan Saeed, the head of the judicial administration department, which the opposition said was considering a corruption investigation into Yameen.

Police said in a statement they were looking to arrest Saeed over an investigation into apartment purchases but the Supreme Court later annulled the police warrant against Saeed, calling it "against established legal procedure".

Police said they were also inquiring about whether family members of Supreme Court Chief Justice Abdulla Saeed and Supreme Court Justice Ali Hameed, who handed down last week's ruling, were involved in the apartment purchases.

On Saturday, senior members of Yameen's ruling party called on authorities to shut down independent TV channel Raajje TV saying it was spreading discord.

In response, the U.S. Embassy in Colombo, Sri Lanka, issued a tweet to say it was "dismayed to hear rumours" about a potential shutdown, and calling it "yet another blow" to freedom of the press.

The political drama in the Maldives, which is made up of 26 coral atolls and 1,192 individual islands, centres on tiny, densely populated Male, the base for all its major institutions.