Lady Gaga has teased fans a mysterious new Revlon project with top Hollywood filmmaker Brett Ratner.

The Rush Hour director took to Instagram on Tuesday (21Feb17) to share a photo of the pair on the set of The Love Project, for which Gaga wore a long, fringed dirty blonde wig.

He didn't share any specific details about the shoot, but posted a second, similar snap online on Thursday (23Feb17) and captioned it, "Another one from #TheLoveProject @ladygaga".

Now Gaga has officially announced her involvement in the venture with a message to followers on Twitter.

"I'm so proud @BTWFoundation (her Born This Way Foundation) and I are partnering with #theloveproject2017," she writes.

The post fails to shed much light on the exact nature of the collaboration, but it appears to involve a social movement as she then called on fans to "Show us your #lovein3words​".

The tweet was accompanied by a 30-second black-and-white video clip showing different kinds of love, including love for family, a significant other, a friend, and for oneself.

The mini video, set to the tune of Gaga's Million Reasons song, ends with the words: "For a million reasons we need love right now. Share yours with #lovein3words".

The Revlon cosmetics logo then appears onscreen, as it's revealed The Love Project will launch on Sunday (26Feb17).

The tag line reads, "Help grow love in the world."

No further details were available at press time.

Gaga founded the non-profit Born This Way Foundation with her mother, Cynthia Germanotta, in 2012 to tackle bullying and boost the confidence of her young fans.