FILE PHOTO: House Oversight and Government Reform Committee Chairman Jason Chaffetz (R-UT) listens to testimony during a committee hearing about the private email server of Democratic presidential nominee Hillary Clinton, used during her tenure as Secretary of State, on Capitol Hill in Washington, U.S., in this file photo dated September 13, 2016. REUTERS/Jonathan Ernst/Files

WASHINGTON (Reuters) - Republican Representative Jason Chaffetz, the chairman of a committee looking into President Donald Trump’s decision to fire FBI chief James Comey, said on Thursday he will depart Congress at the end of next month.

“As you know, after careful consideration and long discussion with my wife, Julie, we agree the time has come for us to move on from this part of our life,” he said in a letter to his Utah constituents.

Chaffetz, a conservative Republican who was first elected to the House of Representatives in 2008, gained prominence as head of the committee that investigated Democratic presidential candidate Hillary Clinton’s use of a private email server while she was U.S. secretary of state.

The House Oversight Committee he heads is one of several congressional panels looking into aspects of Russia’s alleged attempts to influence the U.S. presidential election. In addition to the firing of Comey, it is conducting a probe of whether former Trump National Security Adviser Michael Flynn misled security clearance investigators about Russia contacts.

Chaffetz had considered running for a U.S. Senate seat in the past. A former aide told Reuters last month the congressman may run for governor of Utah in 2020, though no firm decision had been made.