The Energy Secretary Chris Huhne was interviewed by police yesterday over allegations he tried to evade punishment for speeding.
Mr Huhne's ex-wife, Vicky Pryce, was also questioned over claims he asked her to accept penalty points on his behalf in March 2003.
Essex Police confirmed that two individuals had been interviewed in relation to allegations of a speeding offence. But the force did not confirm whether either interview was carried out under caution and stressed that no arrests had been made.
A spokeswoman for Mr Huhne said: "Chris Huhne helped the Essex Police with their inquiries today and looks forward to an early resolution of this issue." Ms Pryce's solicitor said in a statement: "Vicky Pryce met with Essex Police today as part of their inquiry. She continues to do what is necessary in respect of the inquiry but in view of the fact that it is on going it is not appropriate for her or anyone on her behalf to comment further."
Images of Ms Pryce's driving licence published over the weekend indicate that she received three speeding points in the Essex area on the date in question.
But the senior economist, whom Mr Huhne left for another woman last year, is now apparently claiming she was not at the wheel.
Although Mr Huhne has faced calls to resign, David Cameron and his Liberal Democrat Deputy, Nick Clegg, have insisted there is no reason for him to do so at this stage.