UPDATE 2-WPP cuts outlook after falling behind rivals in U.S and UK

The downturn looked all the more concerning after peers such as Omnicom, IPG and Publicis provided solid updates in recent months.

WPP cut its full-year sales and margin outlook as the advertising group's major creative agencies fell behind rivals in North America and Britain, forcing new boss Mark Read to embark on a radical overhaul.

Read, rebuilding the world's biggest ad group following the abrupt departure of founder Martin Sorrell in April, said he would sell a stake in data analytics group Kantar and hold off acquisitions to pump cash into its businesses on Madison Avenue.

Shares in the British company were set to fall at the open, indicative pricing showed, as investors took fright at the sharp drop off in trading, with third-quarter net sales down 1.5 per cent, compared with a rise of 0.7 per cent in the previous three months.

The downturn looked all the more concerning after peers such as Omnicom, IPG and Publicis provided solid updates in recent months.

As a result, the group lowered its net sales full-year guidance, saying it could fall as much as 1 per cent compared with a target of 0.3 per cent growth just three months ago. The operating margin is likely to be down 1 to 1.5 margin points.

WPP, which owns such storied names as JWT, Ogilvy and Y&R, has lost a string of major pitches in recent months, most notably the creative account for Ford to Omnicom's BBDO, which it had previously held for 75 years.

"Turning around WPP requires decisive action and radical thinking, and our performance in the third quarter of 2018 reinforces our belief in that approach," Read said.

The group added that Finance Director Paul Richardson would step down after 22 years in the role.