COLUMBUS, Ohio--House Speaker Cliff Rosenberger announced Tuesday night he will resign his seat May 1 amid questions over an FBI inquiry into his spending and travel.

Rosenberger, a Clinton County Republican who has served as speaker since 2015, has hired a defense attorney after federal agents started an inquiry into his activities, including a trip to London last summer with representatives from the payday lending industry.

In a statement released Tuesday night, Rosenberger said he believes all his actions as speaker have been "ethical and lawful." But he said the inquiry "could take months or even years to resolve," adding "Ohioans deserve elected leaders who are able to devote their full and undivided attention" to issues facing the state.

Rosenberger made the announcement Tuesday night to the House Republican Caucus.

House Speaker Pro Tempore Kirk Schuring, a Canton Republican, will take over as House speaker until the House elects a new speaker to serve through the end of the year.

In a statement, Schuring said Rosenberger's announcement was "emotional" for him.

"Moving forward, my goal will be to facilitate the operations of this institution as smoothly and efficiently as possible," Schuring stated.

Rosenberger, 36, is the first Asian-American to become Ohio House speaker, and he's believed to be the youngest ever to hold the job. An Air Force veteran, Rosenberger previously served as political coordinator in ex-President George W. Bush's administration.

During his time as speaker, Rosenberger has overseen the largest Republican majorities in state history - a job that sometimes put him at odds with various members of his own party as much as it did with House Democrats. Under his leadership, House Republicans passed a number of conservative bills on issues ranging from abortion restrictions to tax cuts, and it unsuccessfully tried to block Gov. John Kasich from accepting Medicaid expansion funds from the federal government.

Rosenberger also became known for his frequent trips to places such as Los Angeles, France, Israel, and England that were paid for out of campaign funds or by outside groups.

The FBI is reportedly looking into Rosenberger's trip to London last August, according to the Cincinnati Enquirer. He was accompanied on the trip by lobbyists Steve Dimon and Leslie Gaines, who work for a title lender trying to block legislation to crack down on payday lenders.

Federal agents are also interested in his ties to heiress Ginni Ragan, a top House GOP donor who rents out a luxury condo to Rosenberger for an undisclosed amount of money, according to the Enquirer.

Rosenberger told the Columbus Dispatch on Tuesday that he has not been personally approached by the FBI nor subpoenaed.

It's not immediately clear how Rosenberger's sudden departure will affect the ongoing - and contentious - race to succeed him between Reps. Ryan Smith and Larry Householder. Rosenberger is considered to be an ally of Smith.