Senate Democrats on Thursday asked US attorney general Alberto Gonzales to remove himself from the corruption investigation involving lobbyist Jack Abramoff, citing Abramoff’s dealings with President George W Bush and others in his administration.

“FBI officials have said the Abramoff investigation ‘involves systemic corruption within the highest levels of government’,” 31 Democrats wrote in a letter to Gonzales.

“In light of your previous service as White House counsel and your close connection to many Administration officials, the appearance of conflict looms large.”

In response, Gonzales said that “we’ve got career prosecutors involved in this investigation as we do in all investigations; these are folks that are not motivated by any political agenda.”

The attorney general made the comment on Fox News Radio.

Justice Department spokeswoman Tasia Scolinos said Gonzales has followed all department guidelines and there is “no reason for him to recuse himself from the investigation at this time”.

Abramoff has pleaded guilty in a fraud and bribery conspiracy case and is cooperating with the investigation into those in Congress and the administration he used to lobby.