Toyota has reportedly agreed to pay over US$1bn to settle a four-year criminal probe over accusations that it misled authorities about unintended acceleration in Toyota cars and subsequent recalls.

US media reports suggest the Justice Department will announce the settlement this week.

The large fine would be part of a deal with the Department of Justice and would be one of the heaviest ever penalties imposed on a carmaker.

Reports also suggest the settlement will include a deferred prosecution agreement that would enable the company to avoid criminal charges.