Rachel Maddow, Maria Shriver, Andrea Mitchell and more than 60 other current and former female NBC News staffers have signed a group letter supporting Tom Brokaw.

'We know him to be a man of tremendous decency and integrity,' said the letter released on Friday, in response to claims that Brokaw made unwanted advances on two women in the 1990s, which the newsman denies.

'Tom has treated each of us with fairness and respect. He has given each of us opportunities for advancement and championed our successes throughout our careers,' the letter said.

Morning Joe co-host Mika Brzezinski was apparently not invited to sign, but tweeted 'Add me to the list' after news of the letter of support.

Rachel Maddow (left) and Maria Shriver (right) are among the female NBC News employees who signed the letter supporting Brokaw in the face of claims he made unwanted advances

NBC News White House Correspondent Kristen Welker (left) also signed. Morning Joe co-host Mika Brzezinski was apparently not invited to sign, but tweeted 'Add me to the list'

Tom Brokaw (pictured) has denied the allegations against him, which NBC News Chairman Andy Lack says the company takes 'very seriously' in a staff memo on Friday

Letter of support for Tom Brokaw from 65 female NBC staffers As professional women, we fully endorse the conversation around abuse of power in the workplace. In the context of that conversation, we would like to share our perspectives on working with Tom Brokaw. We are current and former colleagues of Tom’s, who have worked with him over a period spanning four decades. We are producers, correspondents, anchors, directors, executives, researchers, personal assistants, editors and technical staff. Tom has treated each of us with fairness and respect. He has given each of us opportunities for advancement and championed our successes throughout our careers. As we have advanced across industries — news, publishing, law, business and government — Tom has been a valued source of counsel and support. We know him to be a man of tremendous decency and integrity. Signed, Susanna Aaron Anne Binford Allen Heather Allan Marilyn Altman Liz Bowyer Mary Casalino Christine Colvin Casper Martha Cotton Karen Curry Sara Cusimano Helene Darvick Linda Ellman Judy Farinet Dianne Festa Tammy Fine Mary Laurence Flynn Susan Friedman Soraya Gage Maralyn Gelefsky Cheryl Gould Erika Beck Grothues Colleen Halpin Jody Henenfeld Susan Morris Holey Julie Holstein Julie Huang Peggy Hubble Kiko Itasaka Nancy Jacoby Kat Keeney Ann Kolbell Audrey Beles Kolina Susan LaSalla Rachel Maddow Donna Mastrangelo-Ryan Andrea Mitchell Mauri Moore Frieda Morris Elena Nachmanoff Michele Neubert Kelly O’Donnell Bonnie Optekman Mary Alice O’Rourke Nancy Doyle Palmer Polly Powell Meaghan Rady Elizabeth Vaughan Romaine Amy Rosenberg Stephanie Ruhle Bita Ryan Ruby Shamir Maria Shriver Robin Skolnick Andrea Smith Patricia Sullivan Clare Duffy Swift Yuka Tachibana Bambi Tascarella Zoya Taylor Dee Dee Thomas Anne Thompson Kelly Venardos Kristen Welker Carolyn Wheatley Mary Wolf Advertisement

Earlier on Friday, the head of NBC News acknowledged the allegations against former nightly news anchor Tom Brokaw, calling the claims 'very serious'.

'As you have all seen now in reports from last night, there are allegations against Tom Brokaw, made by a former NBC News journalist, which Tom emphatically denies,' NBC News Chairman Andy Lack wrote in a staff memo on Friday obtained by Deadline Hollywood.

Two women have accused Brokaw of making unwanted advances in the 1990s.

'As we've shown, we take allegations such as these very seriously, and act on them quickly and decisively when the facts dictate,' Lack said.

Despite that assurance, NBC won't be launching a full investigation into the claims, a company source told PageSix.

'She's given her side, and he's responded. They don't feel there's anything left to investigate in the case,' the source said. 'We may make further inquiries if more information emerges.'

NBC Chief Foreign Affairs Correspondent Andrea Mitchell also signed the open letter

Lack's memo also said that findings in an internal NBC probe into Matt Lauer could be ready as soon as next week.

It came as Sacred Heart University President John Petillo said that Brokaw had withdrawn from a planned commencement speech on May 13. 'Mr. Brokaw did not want to distract from the intended and most important focus of the day — our graduating students and their families,' Petillo said in a memo to the community.

Earlier on Friday, Brokaw denied the allegations made by former NBC employee Linda Vester in a scathing email that was sent to the legendary anchor's co-workers and friends on Friday.

'It is 4:00 am on the first day of my new life as an accused predator in the universe of American journalism,' writes Brokaw.

'I was ambushed and then perp walked across the pages of The Washington Post and Variety as an avatar of male misogyny, taken to the guillotine and stripped of any honor and achievement I had earned in more than a half century of journalism and citizenship.'

Brokaw went on to write about the incredible hurt this accusation caused him, as well as the hate he has for his accuser.

The repercussions are already being felt by Brokaw, who elected to cancel his planned commencement speech at Sacred Heart University next month.

Mad: 'I deeply resent the pain and anger she inflicted on my wife, daughters and granddaughters,' said Brokaw (above with his wide Meredith)

'I am angry, hurt and unmoored from what I thought would be the final passage of my life and career, a mix of written and broadcast journalism, philanthropy and participation in environmental and social causes that have always given extra meaning to my life,' noted Brokaw.

'Instead I am facing a long list of grievances from a former colleague who left NBC News angry that she had failed in her pursuit of stardom.'

He continued: 'She has unleashed a torrent of unsubstantiated criticism and attacks on me more than twenty years after I opened the door for her and a new job at Fox news.'

Brokaw then tried to explain what happened between himself and Vester on the night in question, while also criticizing how the press handled the claims.

'Linda Vester was given the run of the Washington Post and Variety to vent her grievances, to complain that I tickled her without permission (you read that right), that I invaded her hotel room, accepted an invitation to her apartment under false pretenses and in general was given a free hand to try to destroy all that I have achieved with my family, my NBC career, my writing and my citizenship,' stated Brokaw.

'My family and friends are stunned and supportive. My NBC colleagues are bewildered that Vester, who had limited success at NBC News, a modest career at Fox and a reputation as a colleague who had trouble with the truth was suddenly the keeper of the flame of journalistic integrity.'

Vester - a war correspondent for the network in the 1990s, who today runs a website for mothers - came forward to accuse legendary newsman who hosted NBC Nightly News for 22 years.

She told The Washington Post and Variety magazine that Brokaw, 26 years her elder, forcibly tried to kiss her twice in 1994 and 1995, while he was the network's star anchor.

Brokaw says only that he met Vester twice, 'both at her request' because she wanted career advice.

Linda Vester (above) has accused Brokaw of assault

'The meetings were brief, cordial and appropriate, and despite Linda's allegations, I made no romantic overtures towards her at that time or any other,' he said in a statement.

Another woman, a 24-year-old production assistant at the time, has also accused Brokaw of sexual harassment dating back to the same period, allegations he also denied.

US television networks have been rocked by a series of accusations as the United States grapples with the cultural shift of the #MeToo movement.

NBC sacked Matt Lauer, the host of its flagship Today program last November. CBS News fired Charlie Rose a few days earlier and Fox News dropped Bill O'Reilly in 2017.

Lauer was the biggest media scalp so far in the US watershed on sexual misconduct, and criticism has mounted against NBC for allegedly not doing enough to counter what some have called a culture of harassment.

'I am speaking out now because NBC has failed to hire outside counsel to investigate a genuine, long-standing problem of sexual misconduct in the news division,' Vester told the Post.

NBC will now start looking into Brokaw's behavior just as the investigation into Matt Lauer nears completion.

Chairman Andy Lack addressed both of those investigations in an internal memo sent on Friday.

'As you have all seen now in reports from last night, there are allegations against Tom Brokaw, made by a former NBC News journalist, which Tom emphatically denies. As we've shown, we take allegations such as these very seriously, and act on them quickly and decisively when the facts dictate,' wrote Lack.

'The same report included claims against Matt Lauer. As you know, since the week we terminated Matt's employment, NBC Universal has been conducting a review, led by general counsel Kim Harris -who has extensive experience in conducting reviews of this kind- with a team of legal and HR leaders. Kim has advised us that the review is nearing its conclusion, and we will have findings and further steps to share with you as soon as next week.'

Lack then closed out the memo by stating: 'Once again, our highest priority is to ensure we have a workplace environment where everyone feels safe and protected. We are absolutely committed to making this a reality--there can be no exception.'