iStock/Thinkstock(WASHINGTON) — President Donald Trump is attacking Senator Kirsten Gillibrand in retaliation for suggesting he resign in the face of sexual harassment allegations made by multiple women.

Over a dozen women have accused Trump of sexual harassment and assault in the years before he was president. Trump has denied the allegations.

Trump called the Democratic senator from New York a “lightweight,” a “total flunky” for Senate Minority Leader Chuck Schumer, D-N.Y., and suggested she would “do anything” for campaign contributions.

“Lightweight Senator Kirsten Gillibrand, a total flunky for Chuck Schumer and someone who would come to my office “begging” for campaign contributions not so long ago (and would do anything for them), is now in the ring fighting against Trump. Very disloyal to Bill & Crooked-USED!” Trump tweeted.

Gillibrand called Trump’s tweet a “sexist smear” and said thoroughly investigating the allegations against him is “the right thing to do.”

“It was a sexist smear attempting to silence my voice and I will not be silenced on this issue and neither will the women who stood up to the president yesterday,” Gillibrand said on Capitol Hill today.

ABC News reached out to the White House for clarification about the president’s remarks but had not received a response at the time of publication.

Gillibrand also responded to the president’s tweet with her own this morning.

“You cannot silence me or the millions of women who have gotten off the sidelines to speak out about the unfitness and shame you have brought to the Oval Office,” Gillibrand wrote on Twitter.

Gillibrand is one of six senators – five Democrats and one independent – who have called for the president’s resignation yesterday and today.

“President Trump has committed assault, according to these women, and those are very credible allegations of misconduct and criminal activity, and he should be fully investigated and he should resign,” Gillibrand said in an interview with CNN Monday.

In the past week, three longtime U.S. congressmen from both parties — Sen. Al Franken of Minnesota, Rep. Trent Franks of Arizona and Rep. John Conyers of Michigan — announced their resignations after they were accused of sexual misconduct. All three men had previously denied the accusations made against them.

The Senate Ethics Committee and the House Ethics Committee have launched investigations into the allegations made against their respective members, Senator Franken, Representative Franks, and Representative Conyers.

On Tuesday, Melinda McGillivray, one of the women accusing the president of sexual harassment and assault, joined Jessica Leeds, Rachel Crooks, and Samantha Holvey in calling for a congressional investigation into Trump.

“I demand that he is subjected to an investigation by the ethics committee. It’s important that we hold this man to the highest standards. If sixteen women have come forward, why hasn’t anything been done? Where is our investigation? I want justice,” McGillvray said on NBC’s “Megyn Kelly Today.”

McGillivray first went public with her allegations in the Palm Beach Post during the campaign. McGillivray claimed that Trump grabbed her rear end in 2003 when she was attending a concert at Mar-a-Lago.

The White House responded to the three women (Leeds, Crooks and Holvey) initially calling for a congressional investigation in a statement Monday.

“These false claims, totally disputed in most cases by eyewitness accounts, were addressed at length during last year’s campaign, and the American people voiced their judgment by delivering a decisive victory,” the White House said in a statement. “The timing and absurdity of these false claims speaks volumes, and the publicity tour that has begun only further confirms the political motives behind them.”

The calls for a congressional investigation into Trump are also being echoed among 56 female Democratic members of the U.S. House of Representatives.

The Democratic Women’s Working Group – led by Democratic Representatives Lois Frankel of Florida, Brenda Lawrence of Michigan, and Jackie Speier of California – said it plans to hold a press conference Tuesday afternoon to call for the House Committee on Oversight and Government Reform to investigate the allegations against Trump.

The group of Democratic female lawmakers sent a letter signed by all its members to Chairman Trey Gowdy, R-S.C., and ranking member Elijah Cummings, D-Md., Frankel announced Monday.

“We cannot ignore the multitude of women who have come forward with accusations against Mr. Trump,” the letter read.

Trump accused Democrats of using “false” and “fabricated” allegations as a way to attack him since they have “been unable to show any collusion” between him and Russia in the 2016 presidential election, which is the focus of a special counsel investigation.

“Despite thousands of hours wasted and many millions of dollars spent, the Democrats have been unable to show any collusion with Russia – so now they are moving on to the false accusations and fabricated stories of women who I don’t know and/or have never met. FAKE NEWS!” Trump tweeted Tuesday morning.

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