Bangladesh on Monday started moving a second group of Rohingya refugees to a controversial flood-prone island in the Bay of Bengal despite opposition from rights activists.

More than 1,600 of the Muslim minority from Myanmar were taken to Bhashan Char earlier this month, and Foreign Minister A.K. Abdul Momen said just under 1,000 were in the latest batch heading for what he called a "beautiful resort".

Buses took the Rohingya from camps in Cox's Bazar, where nearly one million refugees are packed, to Chittagong port where they will be taken to the barren island.

"They are going voluntarily. They are very eager to go Bhashan Char because they have heard from their relatives, those who have gone to Bhashan Char, that (it) is an excellent place," Momen told AFP.

He claimed the island was "100 times better" than the camps, and that the refugees had "appealed" to be taken there.

"Bhashan Char is a beautiful resort. It is an excellent resort. And once anybody goes there, they will love it," the minister added.

Two Rohingya men in the latest group told AFP they were going to the island willingly.

Nur Kamal, a Rohingya from the giant Kutupalang refugee camp, said he was going to be with relatives already at Bhashan Char: "What is the point of staying here (in the camps) without them?"

There are nearly one million Rohingya refugees in packed camps in Bangladesh
There are nearly one million Rohingya refugees in packed camps in Bangladesh AFP / Dibyangshu SARKAR

Serajul Islam said he was going with five family members and was not being forced.

"The way the international community is handling our issue, I don't see any future in the camps," he told AFP from the bus taking him to Chittagong.

"It is better I go and live the rest of my life there in better housing. At least I won't have to think about floods during the rainy season and unbearable heat in the summer."

More than 700,000 Rohingya packed the camps in Bangladesh in 2017 after a deadly Myanmar military clampdown that the United Nations has said could be genocide.

After the first transfer on December 4, several Rohingya told AFP that they were beaten and intimidated to agree to move.

The Bangladesh government eventually wants to put 100,000 Rohingya on the 13,000-acre (56 square-kilometre) island, despite criticism from rights groups because Bhashan Char is so isolated.

The UN said it has not been involved in the process.

"Allegations from within the community about cash incentives being offered to Rohingya families to relocate to Bhashan Char as well as use of intimidation tactics are making the relocation process questionable," said Amnesty International's South Asia campaigner Saad Hammadi.

Foreign minister Momen said critics of the policy were "making up stories".