The jobs are expected to be lost as a result of natural wastage or redundancy.
Around half of the cuts have already been made with the remainder lined up for the end of the year.
Analysts believe up to 3,500 jobs cuts are still to come. According to sources close to the company it is estimated up to 1,500 of these will be compulsory redundancies with a large proportion set to occur in the next quarter.
It is likely the remainder of the job cuts will come through natural wastage.
WPP operations in Europe, the UK and the US are expected to be the hardest hit in terms of cuts. It is believed its companies in Latin America, India and China are likely to remain unscathed.
It is likely that although a target of 6% has been set, the decision over what jobs go will be left to its individual divisions. Worldwide the group employs around 100,000 people.
In December, The Observer reported WPP chief executive Sir Martin Sorrell held budgetary meetings at the end of 2008 where he instructed divisional heads to "trim back" employee numbers where costs exceeded 60% of revenue.
Following this, , the agency set up to service Dell, in February. The decision was taken as a result of the PC manufacturer's reduced marketing spend.
WPP owns international creative networks including JWT and Ogilvy & Mather, and handles global clients including Ford, HSBC and IBM.
Other advertising groups to restructure as a result of the recession include Omnicom, which owns BBDO and PHD.
In December following a downturn in revenue.