"After events of last few days, Mark Penn has asked to give up his role as chief strategist of the Clinton campaign," campaign manager Maggie Williams said in a brief statement on Sunday.

Penn was also being held responsible for the flawed strategy for the campaign which left Clinton trailing Barack Obama for the race to win Democratic nomination for the November Presidential elections.

Colombians too had fired him and his international lobbying and Public Relations firm Burson-Marsteller after Penn said it was a mistake on his part to have met Colombia's Washington ambassador on March 31, describing the remark as insult to the Colombian people.

But his polling firm, Mark and Penn, Schoen and Berland Associates, will continue to provide polling and advice to the campaign.

Communications director Howard Wolfson and newly hired pollster Geroff Garin will now be responsible for designing the strategy.

The revelation of Penn's association, even though it had nothing to do with the campaign, came as a great embarrassment for Clinton and at a time when she is still trying to explain the position she took on the North American Free Trade Agreement (NAFTA).

Several employees' organisation and unions had called for the removal of Penn who, analysts say, was divisive figure inside the campaign though had been associated with the Clintons for over a dozen years.

The New York Times said the Colombian government had hired Penn's firm under a USD 300,000 one-year contract to help secure passage of a bilateral trade treaty with the United States.

Both Clinton and her rival Barack Obama have been strongly opposing the agreement with Colombia and have vowed to vote against it. In fact, both are also demanding renegotiation of NAFTA, arguing it has adversely impact on workers and industry in the United States.

The Times also quoted an unidentified person within the Clinton campaign as saying she was "disappointed" that Penn had taken on Colombia as a client and met with Colombian officials to advise them how to win passage of pace she had publicly denounced.

The Bush administration had completed the Colombia Free Trade Agreement in 2006 and is seeking approval by the Congress.