After announcing 2,000 job cuts last week, Thompson has followed up with a memo to all staff, setting out a new company structure to take effect on 1 May.
Advertising sales will be housed in a new division called regions, with the Americas, Asia Pacific and EMEA "fully accountable for Yahoo's revenue in their own regions".
Thompson wrote: "Our regional sales teams will be the advocate and voice for our advertising customers: listening to them and driving their needs into the products we develop.
"Regional sales must bring urgency and tenacious sales execution to all we do for advertisers. In addition, these teams will leverage our unique and vast data resources to position Yahoo! as the place to connect with users and generate the best, measurable ROI on their adspend."
Parcot, who has been vice-president of sales since 2008, will lead EMEA on an interim basis while Yahoo searches for a new leader for the region.
Rich Riley, who was EMEA managing director until very recently and is moving to New York "soon", has been appointed to lead the Americas region.
Thompson praised Riley and the team "responsible for extraordinary strides in EMEA in recent years, putting the region on a path of consistent engagement and revenue growth".
The regions division will be introduced alongside a consumer division and a technology division.
The consumer division will itself split into a media group led by Ross Levinsohn, a connections group led by Shashi Seth and a commerce group with a leader to be named "shortly".
‘Connections’ encapsulates services such as Mail, Messenger, Flickr and Answers, and Thompson wrote its "highest priority … will be to think well beyond how users search, communicate and share online today".
The technology division includes Yahoo’s ad exchange, the Right Media Exchange (RMX) and user data and analytics.
The company is still searching for a chief marketing officer but has appointed Penny Baldwin as interim leader for its corporate marketing and communications teams.
The chief product officer Blake Irving is leaving the company. The new structure decentralises product development, spreading the function around the three main divisions.
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