The Virgin Group founder told Reuters a cruise division will be set up with two new vessels.
German media reported he was in talks with German and Italian shipyards.
Branson has been seeking investors for the project, including backers from Abu Dhabi. Two thirds of the money will come from banks, however.
Delivery dates from 2017 are being negotiated.
"Most of the money is now committed," he said.
"We will start by building two big ships from scratch and feel the Virgin brand will work very well in cruises."
Gulf Business reported him as saying: “We think we’ve got a concept that is very sexy and it is definitely something that I like to go on and something that my children like to go on.”
The idea is to complement other parts of the business, including UK-based Virgin Holiday Cruises.
The project is likely to be based in Miami.
This is not Branson’s first connection to the world of shipping – his daughter Holly married former Clarksons shipbroker Freddie Andrewes on his Caribbean hideaway Necker Island in 2012.
Andrewes left Clarksons in 2011 to join the Virgin empire.
According to Forbes, Branson has a fortune of $5bn, making him the world’s 289th richest person - and sixth in the UK.
His wealth is well in advance of shipping’s most famous aviator, Stelios Haji-Ioannou. The EasyJet man’s $3.1bn places him at number 551 globally.
