Ministers are said to be looking at vessels no longer in operation, including one from Indonesia, which will be moored in south-west England.
According to The Guardian, the potential move comes amid growing anger from Conservative backbenchers over the use of hotels in their constituencies.
The idea was initially put forward by prime minister Rishi Sunak during his leadership campaign last summer, but was dropped due to concerns the plans could be illegal under the Human Rights Act.
However, sources suggest cruise ships could be registered as hotels rather than detention centres to get around legal challenges.
