Image copyright Getty Images Image caption US Labor Secretary Alexander Acosta

The US labour secretary has defended his past role in striking a plea deal with rich financier Jeffrey Epstein amid calls for his resignation.

Secretary Alex Acosta has come under scrutiny for negotiating a light sentence for Epstein in 2008, when he pleaded guilty to prostitution charges.

Epstein was charged with new sex trafficking charges in relation to allegations from the 2000s on Monday.

Top Democrats in Congress have called for Mr Acosta to resign or be fired.

Epstein was charged on Monday with allegedly running a "vast network" of underage girls for sex, enticing them to visit his Manhattan and Florida mansions between 2002 and 2005.

He pleaded not guilty to charges of sex trafficking and sex trafficking conspiracy, and will remain in jail until his bail hearing on 11 July.

Jeffrey Epstein: What are his famous friends saying?

What did Acosta say?

Mr Acosta had been a federal prosecutor in Florida more than a decade ago when he offered Epstein a deal that allowed the financier to avoid a potential life sentence and instead serve about 13 months in prison. Thanks to a work-release programme, Epstein was able to serve most of that sentence from his office in Palm Beach.

The deal ended the FBI investigation into whether there were more victims than the 36 cited in court documents or if more people took part in the alleged scheme.

Last November, the Miami Herald published an investigation into Mr Acosta's involvement with the 2007 deal that brought the case back into the national spotlight.

During his confirmation hearing in March 2017, Mr Acosta defended the deal, telling lawmakers that it required Epstein to register as a sex offender and go to prison.

On Tuesday, Mr Acosta tweeted that he supported the new investigation and again defended his role handling the original case.

"Now that new evidence and additional testimony is available, the NY prosecution offers an important opportunity to more fully bring him to justice," he wrote, adding:

"The crimes committed by Epstein are horrific, and I am pleased that NY prosecutors are moving forward with a case based on new evidence."

The Department of Labour has told Fox News that Mr Acosta has no plans of resigning due to this scandal.

What has President Trump said?

At the White House on Tuesday President Donald Trump told reporters of his labour secretary: "I feel very badly, actually, for Secretary Acosta."

Mr Trump said that the first time he met Mr Acosta was when he chose him for the cabinet position, and emphasised how much time had passed since the 2008 plea agreement.

Media playback is unsupported on your device Media caption President Trump distances himself from Jeffrey Epstein - and defends role of Alex Acosta

"What happened 12 or 15 years ago, if you go back and look at everybody else's decisions, I would think you'd probably find that they would wish that they maybe did it a different way," he said.

"But we're going to be looking at that and looking at it very closely," Mr Trump continued.

Mr Trump added that he knew Epstein as a "fixture in Palm Beach", where Mr Trump owns a golf resort.

"I had a falling out with him a while ago," he said, adding that they parted ways around 15 years ago.

"I was not a fan," he added.

Who is calling for Acosta to resign?

During a speech from the Senate floor on Tuesday, Democrat Chuck Schumer said Mr Acosta should be fired if he does not resign.

"It is now impossible for anyone to have confidence in Secretary Acosta's ability to lead the Department of Labor," Mr Schumer, the top Democrat in the Senate said during a floor speech on Tuesday.

"We cannot have as one of the leading appointed officials in America someone who has done this, plain and simple."

Senator Schumer's comments came a day after Speaker of the House of Representatives Nancy Pelosi tweeted after Epstein's preliminary hearing that Mr Acosta "must step down".

The California congresswoman said Mr Acosta "engaged in an unconscionable agreement" with Epstein and prevented young victims from "seeking justice".

Senator Tim Kaine of Virginia and Florida Congresswoman Debbie Wasserman Schultz are among other Democrats who have called on Mr Acosta to resign.

A number of 2020 Democratic presidential hopefuls, including Senators Kamala Harris, Amy Klobuchar, Kirsten Gillibrand and Cory Booker, have echoed the same.

Image copyright Getty Images Image caption Epstein's opulent New York City home was raided over the weekend

Image copyright Getty Images Image caption A protest group called "Hot Mess" outside the Manhattan courthouse

Who is Jeffery Epstein?

The New York native taught mathematics and physics at Manhattan's private Dalton School. He moved into finance in 1976, working as an options trader for investment banking company Bear Stearns. Within four years, he was made a limited partner.

He then went on to found his own financial management firm J Epstein & Co, reportedly managing the assets of clients with more than $1bn (£798m) in net worth.

In 1996, he changed his company's name to The Financial Trust Co and based it in the US Virgin Islands for tax purposes.

His lavish lifestyle, along with the secrecy surrounding his client list and other details of his business, earned Epstein a reputation as a mysterious moneyman.

Reports of his current wealth vary, with his Virgin Islands-based firm generating no public records.

According to Florida court records, Epstein also maintains properties in the US Virgin Islands, Paris and Mexico.

Image copyright Reuters Image caption Epstein has a residence in Palm Beach

The financier rubbed elbows with many of America's rich and powerful, including former president Bill Clinton, President Donald Trump and Prince Andrew.

In a 2002 interview, Mr Trump called Epstein a "terrific guy" who he had known for 15 years.

"He's a lot of fun to be with," the president said at the time. "It is even said that he likes beautiful women as much as I do, and many of them are on the younger side."

On Monday, a spokesman for Mr Clinton said he "knows nothing about the terrible crimes".