(Adds no comment from WPP, more details of the report)
LONDON, July 21 (Reuters) - Chinese conglomerates Alibaba and Tencent are involved in talks to buy a minority stake in advertising giant WPP's Chinese unit, Sky News reported on Saturday, citing unidentified sources.
Sky News said the firms, along with China Media Capital Holdings (CMC), were in early-stage discussions about buying roughly 20 percent of WPP China in a deal that would value the business between $2 billion and $2.5 billion.
A spokesman for WPP declined to comment.
WPP, the world's biggest advertising group, is in the midst of a leadership change.
Founder Martin Sorrell left in April following a complaint of personal misconduct. Executive Chairman Roberto Quarta said last month that the search for Sorrell's replacement was well-advanced.
The China deal, which could take several months to conclude, would see WPP pool its Chinese agency operations into a new holding company and retain majority ownership and control, Sky News said.
The report said the deal had been brewing since before Sorrell left, and that Quarta went with co-chief operating officer Andrew Scott to China this month to continue talks. (Reporting by Alistair Smout Editing by Edmund Blair and John Stonestreet)