A Republican lawmaker is vowing to begin contempt-of-Congress proceedings against former President Bill Clinton after he failed to show up on Tuesday to testify before a committee investigating Jeffrey Epstein.

House Oversight Committee Chairman James Comer told reporters he would start proceedings against Clinton next week, and could do the same against former Secretary of State Hillary Clinton if she fails to answer questions on Wednesday.

The committee had issued subpoenas for both Clintons to testify about the late convicted sex offender.

Lawyers for the Clintons called the subpoenas "unenforceable", and said they had already provided the "limited information" they had about Epstein.

Bill Clinton has never been accused of wrongdoing by survivors of Epstein's abuse, and has denied knowledge of his sex offending.

In a statement on Tuesday, Comer said the subpoenas to the Clintons were voted on in a "bipartisan manner".

"We communicated with President Clinton's legal team for months now, giving them opportunity after opportunity to come in, to give us a day, and they continue to delay, delay, delay, to the point where we had no idea whether they're going to show up today or not," he said.

The Clintons contended the subpoenas - legal orders to provide testimony - "are nothing more than a ploy to attempt to embarrass political rivals, as President Trump has directed".

In a letter to Comer, lawyers for the Clintons said they had communicated "proactively and voluntarily" with the committee and that the subpoenas were "untethered to a valid legislative purpose, unwarranted because they do not seek pertinent information, and an unprecedented infringement on the separation of powers".

Bill Clinton appears with Epstein and at the late financier's estate in photographs that were recently released by the US Department of Justice after Congress passed a law requiring the agency to release material related to investigations of Epstein.

One picture shows the former president swimming in a pool, and another shows him lying on his back with his hands behind his head in what appears to be a hot tub.

Clinton was photographed with Epstein several times over the 1990s and early 2000s, before Epstein was arrested for sex-trafficking.

Clinton spokesman Angel Ureña said when the photos were released last month that they were decades old and Clinton stopped associating with Epstein before his crimes came to light.

A spokesperson has previously acknowledged that Bill Clinton took four trips with staff on Epstein's private plane in 2002 and 2003, and met with Epstein in New York in 2002. Clinton also visited Epstein's New York apartment around that time.

Citing flight logs, US media have previously reported Clinton flew on Epstein's jet more than two dozen times, occasionally without his Secret Service detail.

Congress has the authority to detain someone until they comply with a subpoena, send a contempt certification to the justice department for prosecution or ask a court to force compliance.

"If the court finds that the party is legally obligated to comply, continued non-compliance may result in the party being held in contempt of court," according to the nonpartisan Congressional Research Service.

"Where the target of the subpoena is an executive branch official, civil enforcement may be the only practical means by which Congress can effectively ensure compliance with its own subpoena."

Criminal contempt of Congress is a misdemeanour offence punishable by a fine up to $100,000 (£74,500) and imprisonment up to a year.

Over the last year, lawmakers from both parties have pushed to learn about Epstein's associations with powerful people and passed a law demanding that the justice department release all files from federal investigations into the sex offender by the middle of December.

After the department only released a portion of the files, the legislation's authors - Republican Thomas Massie and Democrat Ro Khanna - went to court last week and asked a federal judge to appoint a special master to make sure the government complies with its requirements. (BBC)

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