Jeffrey Lucy has resigned as an Australian Securities and Investments Commission (ASIC) commissioner after only five months to return to the Financial Reporting Council (FRC) for a three-year part-time post as Chairman.

Mr Lucy was appointed to a two-year tenure as ASIC commissioner in May this year after serving three years as the regulator's chairman.

He was FRC Chairman from 2001 to 2003 before joining ASIC as Deputy Chairman.

Federal Treasurer Peter Costello has appointed Mallesons Stephen Jaques partner Belinda Gibson as the new commissioner.

She will take up her post at ASIC on November 5, while Mr Lucy will officially depart on December 10 to join the FRC with immediate effect.

The FRC is responsible for overseeing accounting and auditing standards and monitoring the effectiveness of auditor independence. It reports directly to the Treasury.