Foreign Secretary Boris Johnson said in London Friday that Britain "regrets that the Maldives has chosen to leave" the Commonwealth.
The Maldives said Thursday it had decided to leave the group of mostly former British colonies after what it called "unjust and unfair" criticism of its human rights record.
In September the 53-nation group had warned the small Indian Ocean nation that it risked suspension from the Commonwealth if did not improve levels of democracy and human rights in the country.
But in a statement Thursday, the Maldives accused the Commonwealth of wanting to "become an active participant in the domestic political discourse in the Maldives, which is contrary to the principles of the Charters of the UN and the Commonwealth."
Britain will not cut ties with the Maldives. "We will continue to work with the Maldives government to help strengthen democracy, particularly freedom of speech and the media and independence of the judiciary," Johnson said in his Friday statement.
"The stability of the country must be central to what happens next," he said.
Amnesty International said the country's authorities "should address their own human rights situation rather than lash out at legitimate criticism."
"Human rights have been in a complete freefall in the country over the past few years," said Champa Patel, Amnesty's South Asia director.
"The government has locked up opponents through politically motivated trials and led an unprecedented crackdown on independent media," Patel said in a statement.
The Maldives government accused the Commonwealth of using the country to "increase the organization's own relevance and leverage in international politics."
The decision to leave was "difficult, but inevitable," it said.
The Commonwealth Secretary-General Patricia Scotland responded in a statement on Thursday, saying she was sad and disappointed by the Maldives' decision to leave.
"We hope that this will be a temporary separation and that Maldives will feel able to return to the Commonwealth family and all that it represents in due course."
The Maldives are a group of islands with a population of some 345,000.
Islam is its official religion and the legal system is based on Islamic law.
The country has close ties to India but has increased economic links to China in recent years.