Aaron Schock, US lawmaker with 'Downton office,' resigns
Representative Aaron Schock is resigning after questions over his use of campaign and public funds.
Mr Schock, 33, is under fire for his lavish spending, using public funds on donor-provided private flights and property transactions involving political contributors.
A congressional ethics investigation was reportedly under way.
The Republican from Illinois has served in Congress since 2009.
In a statement, Mr Schock said he would step down on 31 March, and was doing so with a "heavy heart".
"Constant questions over the last six weeks have proven a great distraction that has made it too difficult for me to serve the people of the 18th District with the high standards that they deserve and which I have set for myself," Mr Schock said, according to Politico, which first reported the story.
Mr Schock was the focus of a Washington Post story about his congressional office, which was decorated in the style of Downtown Abbey.
While Mr Schock repaid the government $40,000 (£28,500) for the office renovation, it was the first in a series of increasingly serious headlines about his spending of public and campaign funds.
The Associated Press (AP) used geolocated data from the Illinois lawmaker's Instagram account and his flight records to pin the congressman for more than $40,000 of expenses taken to cover the cost of private flights.
While that is within the rules of Congress to use office funds in this way, it was not in 2013, the year investigated by the AP.
Separately, Mr Schock came under scrutiny for multiple property deals closely related to political donors.
On Monday the AP confirmed that the Office of Congressional Ethics had reached out to Schock's associates to interview them.
And Politico reported on Tuesday Mr Schock billed the federal government and his campaign for 170,000 miles (274,000km) on a personal vehicle over four years. But the vehicle only had about 80,000 miles recorded when he returned it.
Top House Republican John Boehner said Mr Schock "has put the best interests of his constituents and the House first."
"I appreciate Aaron's years of service, and I wish him well in the future."