Travel agents are expected to struggle to supply enough gay honeymoons when same-sex weddings become legal next month.

From 5 December, gay and lesbian couples will be able to formalise their relationships with local authorities under the Civil Partnership Bill.

But Fiona Jeffery, exhibition director at the World Travel Market show in London, said she believed the travel industry was not prepared for the rise in demand.

"Unlike the big banks and the technology companies, the travel industry simply has not planned ahead for the implementation of this Bill," she said. "There's no doubt this will trigger a new and completely different demand for tour operators, and the industry has not even got off the starting blocks."

A total of 274,000 gay couples in the UK are expected to marry, says a report published yesterday by Out Now Consulting, a marketing agency.

"Gay honeymoons are going to be booming but the travel industry has to do much more if it is to capitalise on the new developments," said Ian Johnson, the author of the report.