NEW YORK -- U.S. President Donald Trump sharply increased the amount of money he gave away through his foundation last year as the charity drew scrutiny during the campaign.

A 2016 tax return posted on the non-profit monitoring website GuideStar shows that the Donald J. Trump Foundation gave away $3.1 million, more than it did in the prior three years combined. Most of that money came from a fundraiser for veterans held by Trump early last year.

Trump drew criticism during the campaign after news organizations raised questions about his foundation's use of funds and reported that he often did not follow through on promised donations.

New York Attorney General Eric Schneiderman launched an investigation into the foundation last year after reports that Trump used the charity to settle lawsuits, made an illegal $25,000 political contribution to a group supporting Florida's attorney general, and purchased items such as a painting of himself that was displayed at one of his properties. A tax return made public after the election showed the foundation itself admitted to violating IRS regulations.

Trump promised in December to dissolve the charity to avoid conflicts of interest, but Schneiderman has said the charity cannot close while the investigation is going on. A spokeswoman for the Trump Foundation said Monday that the charity is working with the attorney general's office to close down and will distribute the rest of its money at the "earliest possible time."

The money raised for veterans last year went to several veterans' groups including the Green Beret Foundation and Veterans in Command, which provides shelter for homeless veterans. The foundation also gave to Partners for Patriots, which provides service dogs for disabled veterans, and Racing for Heroes, which uses motorsports as recreational therapy for veterans.

Trump has pledged to donate his annual $400,000 salary as president to charity.

Major donors to the foundation include Phil Ruffin, the casino billionaire who partnered with Trump on a Las Vegas residential tower that bears the president's name. He gave $1 million to the charity last year.

Another donor is the Daryl and Steven Roth Foundation, which gave $50,000. Steven Roth is CEO of Vornado Realty Trust, which owns two office buildings with Trump.

Ivanka Trump, the president's daughter, donated $100,000 to the foundation.

The Washington Post last year reported that records showed Trump made $8.5 million in pledges to charitable groups in the 15 years before his campaign but paid out only about $2.8 million.

Aside from his foundation, Trump donated $1miillion to the Marine Corps-Law Enforcement Foundation, a charity run by a friend