Quantum PR has been hired to handle the six-month project to raise the brands' profile in the consumer press.
This is the first time Warnaco, which filed for bankruptcy last year and is in the process of restructuring, has sought to push the brands in the UK.
Agency MD Sam Denny-Hodson oversees the account team, which includes Jo McConnell as account director.
She said: 'We will concentrate our strategy on the consumer press and also on product placement.'
Quantum already handles PR for Warnaco brands Warner's and Bodyslimmer's. It has worked with the company since the agency was formed six years ago.
The Quantum team reports to CK Underwear and Men's Accessories Europe president Thomas Axmacher.
Warnaco filed for bankruptcy protection in June 2001, blaming a slowing US economy and increased competition. However, analysts at the time blamed a policy in the late 1990s of marketing to department stores, rather than increasingly popular discount stores.
A £400m financing package has since been approved and the company now has until the end of next month to file its plan for recovery.