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* FTSE 100 up 0.2 pct at 6,586.91 points
* Upbeat Publicis results lift rival WPP
* Renewed vague bid talk boosts M&S
By Sudip Kar-Gupta
LONDON, July 18 (Reuters) - Britain's benchmark equity indexedged up on Thursday, as major advertising group WPP rose after upbeat results from one of its rivals, while renewedbuyout bid speculation boosted retailer Marks & Spencer.
The blue-chip FTSE 100 edged up by 0.2 percent, or14.98 points, to 6,586.91 points in early session trade.
WPP, which has one of the biggest market capitalisations inthe FTSE 100, rose 2.5 percent to give one of the biggest liftsto the index, which was also helped by French rival Publicis posted higher sales growth.
M&S, which has been the subject of on-off bid speculation inthe UK media, also rose 2.3 percent to feature among thebest-performing FTSE 100 stocks after the Daily Mail newspaperreported "revived U.S. bid talk" surrounding the company.
"I like M&S as a firm, but I wouldn't buy it at theselevels, especially with the bid rumours built into the price. Ifno bid arrives, you'd be caught off-side," said EGR Brokingmanaging director Kyri Kangellaris.
The FTSE 100, which is up by around 12 percent since thestart of 2013, raced to a 13-year high of 6,875.62 points inlate May.
It then slipped back in June on expectations that the U.S.Federal Reserve would eventually scale back economic stimulusmeasures that had helped drive the global equity rally this yearbefore then recovering in July.
Yet despite the July recovery, the FTSE 100 is still downsome 4 percent from those May peaks, and Hartmann Capital traderBasil Petrides said he would err on the side of betting on aminor, short-term fall rather than a rise.
"I still think we have a softer bias for now," he said.
