Shares in

Young & Rubicam


surged Friday after

WPP Group


confirmed that talks between the two advertising companies about a possible combination had resumed.

Y&R shares closed up 4 1/2, or 9%, at 54 1/8. WPP's American depositary receipts closed down 5 1/2, or 7%, at 75 1/2.

The two companies have been in on-again, off-again discussions for months. Earlier this week, talks

broke off again over price, and French ad holding company

Publicis S.A.

emerged as the front-runner to buy Y&R.

The circumstances swirling around the three advertising giants changed yet again Friday, however. "The board of WPP announces that the recently terminated discussions with Young & Rubicam have been resumed," the company said in a statement to the

London Stock Exchange

. "There can be no assurances that a transaction will be agreed.''

Publicis, which only emerged as a potential suitor last week, said Tuesday it was studying opportunities with Y&R, but that a takeover deal was not imminent.

A deal between Britain's WPP, which acquired both

Ogilvy & Mather


J. Walter Thompson

through hostile takeovers in the late 1980s, and New York-based Y&R would create the world's largest advertising company.