The company, formed from last year's $40bn (£25.6bn) merger of Chevron and Texaco, had promised Wall Street that the deal would produce at least £768m in annual cost savings, with marketing services one of the areas earmarked for rationalisation.
ChevronTexaco's decision to hand Y&R the European advertising business, which will also involve a significant billings boost for the Wunderman integrated network, strengthens WPP's presence in the oil sector. Sister agency J Walter Thompson already handles the global ad task for Shell.
In the UK, the shift is likely to see Rainey Kelly Campbell Roalfe/Y&R and Harrison Troughton Wunderman take on the domestic business, which focuses on the 1000-strong chain of Texaco service stations and fuel products.
Y&R, which was already a ChevronTexaco rostered network in several markets, pitched for the business against Omnicom's BBDO Worldwide, McCann-Erickson and Bates Worldwide. Texaco's UK office could not confirm the Y&R appointment as Marketing went to press.
Texaco's most recent UK ad was a TV spot created by HHCL to promote the brand's promotional tie-up with Disney film Lilo & Stitch. Its marketing strategy had also focused on its sponsorship of ITV's Formula One coverage, which ended last season.