Kevin Rudd's prime ministerial ambitions have forced a second member of his family to sell a business.

As the polls continue to point to a Labor victory in the federal election, Mr Rudd's older brother, Greg, has announced he is selling his lobbying business, Open Door Consulting.

A statement posted on the Open Door website said: "Due to a perceived conflict of interest regarding Mr Greg Rudd's involvement with the federal aspect of the Open Door Consulting business, Greg has made the difficult decision to withdraw as the Managing Director and sole equity holder in Open Door Consulting Pty Ltd."

Two Open Door employees, Andrew Soter and Andrew Hazell, will take over "total ownership" of the business on January 1, 2008.

"It will be a seamless transition and business as usual for current and future clients," the statement said.

This year, Kevin Rudd's wife, Therese Rein, was forced to sell the Australian arm of her recruitment company, Ingeus, to avoid possible conflicts of interest.

Greg Rudd, a former staff member in the Hawke-Keating government, started Open Door Consulting after Labor lost power in 1996.