Trump sends charged tweets amid calls for hearings over assault claims

As the #MeToo movement of harassment victims speaking out has gathered pace in the worlds of politics and entertainment, US President Donald Trump has found himself once again in the crosshairs.

So far, more than 100 members of Congress have called for a probe into allegations of sexual misconduct against Trump, including his target on Tuesday, Senator Kirsten Gillibrand.

Three women who claim they were sexually harassed by Trump before he ran for president urged lawmakers Monday to open the inquiry into his alleged misconduct, which includes unwanted kissing, touching and groping.

Trump struck back in a series of tweets -- and seemingly accused Democrats of egging on the women who addressed reporters about the alleged harassment.

He also antagonized several female Democrats by calling Gillibrand a "lightweight senator... who would come to my office 'begging' for campaign contributions not so long ago (and would do anything for them)."

Gillibrand retorted by calling Trump's social media post "a sexist smear" that sought to silence her amid a renewed chorus of women calling for Trump to be investigated over past sexual impropriety.

Gillibrand fired back with a tweet of her own.

"I will not be silenced on this issue. Neither will the women who stood up to the president yesterday," she told reporters.

White House spokeswoman Sarah Sanders said only those with minds "in the gutter" would see the tweet as suggestive.

"There is no way that this is sexist at all," Sanders said.

Democrats fire back

Democrats rushed to Gillibrand's defense, including Senator Elizabeth Warren, who herself has been a target of Trump's taunts, and who used incendiary language of her own.

Gillibrand has spent years in Congress pressing for broader protections for victims of sexual abuse, and demanding that the military and government agencies be held accountable.

Congresswoman Jackie Speier, who helped jumpstart the #MeToo movement on Capitol Hill by acknowledging that she had been sexually harassed as a congressional staffer years ago, called Trump's tweet "grotesque."

Senator Tim Kaine - Hillary Clinton's running mate in 2016 - branded it "low-life behavior."

Congressional resignations over sexual misconduct

Three US lawmakers announced their resignations from Congress last week over sexual harassment allegations, including Democratic Senator Al Franken of Minnesota.

Addressing the Senate, Franken said he was keenly aware of the "irony in the fact that I am leaving while a man who has bragged on tape about his history of sexual assault sits in the Oval Office”.

More than a dozen women have come forward with claims of misconduct by Trump, who boasted in a video tape that surfaced during the campaign that he could kiss and grope women with impunity, because of his celebrity.

Congress is called on to investigate Trump

A letter signed by nearly 60 female Democratic lawmakers made reference to the recording, saying at least 17 women have charged the president with sexual misconduct, and urged the House of Representatives oversight committee to probe the misconduct claims.

Congresswoman Lois Frankel, who authored the letter from dozens of female lawmakers calling on the House oversight committee to investigate Trump, said the surge of women publicizing their harrowing accounts of harassment could mark an important turning point.

"The Me Too movement has arrived," Frankel said.

"Sexual abuse will not be tolerated, whether it's by a Hollywood producer, the chef of a restaurant and member of Congress, or the president of the United States."

Responding to mounting calls for his resignation over additional sexual misconduct, the president framed the effort as a Democratic plot to remove him from office over illegitimate claims.