TNS confirmed that jobs are at risk and that the furlough has been introduced to help reduce the risk of further job cuts.
The redundancies are the result of adverse economic conditions, but also a side-effect of the merger of TNS Custom, TNS's bespoke research division, with Research International.
Andrew Czarnowski, TNS UK's chief executive, told Brand Republic: "Like most UK businesses we have not been immune to the effects of the economic downturn.
"It is with reluctance that a small number of TNS UK Custom employees have been notified that their roles are at risk of redundancy.
"In addition, employees are being asked to take two weeks' unpaid leave between now and December 2009 to reduce potential for further redundancies."
"The actions we are taking are balanced so that we can address our short-term business pressures and retain our talent to ensure that we are in the strongest position to respond to recovery from the recession."
WPP Group acquired TNS last October for £1.9bn and the business now falls under the remit of WPP's Kantar Group.
Job cuts are affecting all businesses across the WPP empire. In May, it was revealed that WPP planned to cut 7,200 jobs this year in response to clients slashing marketing budgets.
The company had already made around half of the job cuts as part of plans to reduce its global workforce by 6% by the end of 2009.
Yesterday, shares in WPP fell 7%, the largest FTSE 100 fall, after analysts suggested that the group's results next month will be disappointing.
Analysts said that while WPP's revenues are expected to recover in the second half of 2009, there could be little in the way of growth next year and that its first-half results could show a decline in profitability.
The predictions caused WPP's share price to lose 29p and fall to 384.5p.
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