CHI pitched against Fallon and HHCL/Red Cell to win the account. NatMags has set aside a £10 million budget for the launch marketing activity.
The NatMags managing director, Duncan Edwards, said the launch, named Project Reveal, was in the early stages of development.
Edwards added: "I can confirm that we are looking at all frequencies, including the women's weekly sector. One project, to which we have given the working title Reveal, is in its infancy."
Jessica Burley, the group publishing director of NatMags' women's home and lifestyle group, is leading the project team for the launch, which is one of a number of projects NatMags is developing.
"Like all businesses, we are constantly looking at new opportunities and I would like to stress that our focus is not exclusively on the weekly market," Edwards said.
Reveal is at such an early stage that NatMags has not made public details of a cover price, launch date or pagination. However, it is recruiting a core team to work on the launch.
It will be the first celebrity weekly glossy to be produced from the NatMags stable. As well as Closer, Emap publishes Heat, while Now is published by IPC Media.
As well as launching into the weekly market, NatMags is also looking at boosting the circulation of its flagship women's monthly, Cosmopolitan, with a relaunch designed to appeal to a younger readership.
The publisher is looking for an advertising agency to handle the relaunch of the title. It has been working with Rise Communications on developing a strategy.
NatMags has also begun working with Rodale International to set up a joint venture called NatMag Rodale Ltd, which will publish Rodale's Men's Health and Runner's World titles.