The Gold Star mother of an Army Special Forces sergeant killed in Niger is backing up a Democratic congresswoman's version of a condolence phone call between family members and Donald Trump, saying the president 'disrespected' them.

Rep. Frederica Wilson had told reporters Trump dismissively said to Sgt. La David Johnson's widow Myeshia that he 'knew what he signed up for' by enlisting, adding that 'when it happens it hurts anyway.'

'Yes the statement is true,' Johnson's mother, Cowanda Jones-Johnson, told the Associated Press on Wednesday.

'I was in the car and I heard the full conversation. Not only did he disrespect my son,' she said, but Trump also disrespected the dead soldier's father and his widow.

Jones-Johnson, who was listening on speakerphone, also told The Washington Post that 'President Trump did disrespect my son and my daughter, and also me and my husband.'

Asked if Rep. Wilson's recollection of the call was accurate, she replied: 'Yes.'

But Trump spent some of Wednesday disputing the account that Jones-Johnson confirmed.

Trump tweeted Wednesday morning that Wilson 'totally fabricated what I said to the wife of a soldier who died in action (and I have proof).'

When asked what evidence the White House had to back up Trump's dissent, press secretary Sarah Sanders said there were no recordings of the call 'but there were several people in the room from the administration who were on the call, including Chief of Staff Gen. John Kelly.'

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The late Army Sgt. La David Johnson is pictured with his mother Cowanda Jones-Johnson, who is backing up Rep. Frederica Wilson's account of a condolence call in which Donald Trump told her the slain solider 'knew what he signed up for'

President Trump phoned Myeshia Johnson on Tuesday afternoon to give his condolences over the death of her husband Sgt. La David Johnson

Trump denied making the insensitive remark, tweeting on Wednesday that the congresswoman 'totally fabricated' it

Congresswoman Frederica Wilson heard Trump's call on speakerphone and made the rounds on television to claim Trump 'has a brain disorder, and he needs to be checked out. ... We should be praising his family, not insulting them'

Trump called Wilson a liar, telling reporters at the White House: 'I didn't say what that congresswoman said, didn't say it at all. She knows it'

Asked what the 'proof' was that he tweeted about, Trump dared Wilson to repeat her claim: 'Let her make her statement again and then you'll find out.

White House press secretary Sarah Sanders said Wednesday that there aren't any recordings of the call, but several administration officials were in the room and heard what Trump said

'The president's call, as accounted by multiple people in the room, believe that the president was completely respectful, very sympathetic, and expressed the condolences of himself and the rest of the country,' Sanders said, 'and thanked the family for their service, commended them for having an American hero in their family, and I don't know how you could take that any other way.'

She blasted the media for the 'disgrace' of turning Trump's condolences into a scandal, and hammered Wilson for how 'she's politicized this issue.'

Cowanda Jones-Johnson told a reporter that 'President Trump did disrespect my son and my daughter, and also me and my husband

'This is about a president who loves this country very much, who has the greatest level of respect for men and women in the uniform, and wanted to call and offer condolences to the family,' an annoyed Sanders added.

'And I think to try to create something from that, that the congresswoman is doing, is frankly appalling and disgusting.'

Appearing on 'The View,' Wilson dared Trump to provide evidence, declaring that 'President Trump is a liar ... If he was taping the conversation, bring it on!'

At the White House, Trump insisted to reporters that Wilson was no longer repeating her claim – not knowing that she was doing so that very hour on 'The View.'

'I didn't say what that congresswoman said, didn't say it at all. She knows it, and she now is not saying it,' Trump claimed, with his arms crossed.

'I did not say what she said, and I'd like her to make the statement again because I did not say what she said.'

Asked what the 'proof' was that he tweeted about, he said: 'Let her make her statement again and then you'll find out. Okay. Let her make her statement again and then you'll find out.'

A White House spokesperson did not respond to a question Wednesday about what Trump's evidence consists of, and the president hasn't produced any.

Calling in to 'The View,' Wilson said Trump is 'a liar' and challenged him to produce a recording of his phone call with Johnson

Johnson, who is expecting the couple's third baby in January, later sobbed as she leaned over her husband's coffin

Wilson spoke to CNN early on Wednesday morning, citing several people in the car who were aware of Trump's remarks and saying: 'This gentleman has a brain disorder, and he needs to be checked out. ... We should be praising his family, not insulting them.'

'I have no reason to lie about the President of the United States,' she insisted, citing 'her aunt, her uncle, my press person, the driver [and] the master sergeant' as witnesses who heard Trump speak.

Sgt. La David Johnson, 25, was among the four US troops who were killed in Niger nearly two weeks ago during an ambush

She said Trump 'should be asking for an apology, and asking, giving her some empathy and love, and wrapping his arms around this family ... instead of calling me a liar and claiming everyone else in the car is a liar.'

'We're grieving! This is a grieving community!' Wilson exclaimed. 'It is disgraceful for him to even tweet about this.'

La David Johnson's sister-in-law Antionette Manuel told DailyMail.com the U.S. military had instructed her family not to speak with the media.

'I'm sorry, I have to talk to my sister. We can't talk about it yet. None of the family can,' Manuel, 28, said outside her family's home in Miami Gardens, Florida.

Wilson had said she was sitting beside the grieving widow Myeshia when she took the call, while they were on their way to Miami International Airport where Johnson's remains were arriving on a commercial flight.

On MSNBC, she said that the call 'was horrible. It was insensitive. It was absolutely crazy. Unnecessary. I was livid!'

And the widow, she recalled, 'was in tears. And she said, "He didn't even remember his name!"'

'Yes, he said it,' Wilson had told WPLG on Tuesday evening.

'It's so insensitive. He should have not have said that. He shouldn't have said it.'

Also travelling in the car to the airport on Tuesday was Miami-Dade Commissioner Barbara Jordan, who said she was shocked by what she heard.

TRUMP DOUBLES DOWN The president told reporters late Wednesday morning at the White House: 'I didn't say what that congresswoman said, didn't say it at all. She knows it, and she now is not saying it. I did not say what she said, and I'd like her to make the statement again because I did not say what she said. 'I had a very nice conversation with the woman, with the wife, who is – sounded like a lovely woman. Did not say what the congresswoman said. And most people aren't too surprised to hear that. Then, asked what the 'proof' was that he tweeted about, Trump said: 'Let her make her statement again and then you'll find out. Okay. Let her make her statement again and then you'll find out.' Advertisement

Rep. Frederica Wilson slammed Trump for his 'insensitive' comments regarding the death of Sgt. Johnson

WHO IS REP. FREDERICA WILSON? Florida Rep. Frederica Wilson, a reliably liberal Democrat, has been a member of Congress since 2011. Wilson, 74, was among more than 60 Democrats who skipped President Trump's inauguration in January. At the time she said her god-daughter's wedding conflicted with the event. The perennially cowboy-hatted lawmaker has earned a reputation for missing other events as well – notably, votes on the House floor. The Broward New Times reported in 2011 that no member of Florida's congressional delegation missed more votes that year than she did. Wilson skipped 117 out of 948 votes that year. Her tenure in Congress has led her to weigh in on issues of race and social justice, including in 2013 when she authored a congressional resolution 'honoring the life of Trayvon Martin' and calling the case one of 'racial profiling.' And she told a town hall meeting in 2011 that conservative Republicans were responsible for the high rate of African-American unemployment. 'Let us all remember who the real enemy is ... the real enemy is the Tea Party ... the Tea Party holds the Congress hostage,' she said. Wilson is among the Florida congressional delegation's wealthiest members, reporting more than $1.5 million in assets on her government financial disclosure form. Advertisement

'What the family wants to hear is words of encouragement, words of how he fought for his country, what his sacrifice meant for this country ... not, "You know what you signed up for",' she said on MSNBC's 'Morning Joe' program.

Johnson's mother, Cowanda Jones-Johnson, told The Washington Post that she heard Trump's words, and that 'President Trump did disrespect my son and my daughter, and also me and my husband.'

Asked if Wilson's recollection of the call was accurate, she replied: 'Yes.'

Heartbreaking footage later showed Johnson, who is expecting the couple's third baby in January, sobbing as she leaned over her husband's flag-draped coffin.

The couple's six-year-old daughter stood by the coffin with her mother, while their two-year-old son waited in the arms of a relative standing nearby.

Former first daughter Chelsea Clinton reacted on Twitter to news of Trump's phone call saying: 'Mrs Johnson, I cannot begin to imagine your loss. Your family & all who mourn Sgt. Johnson are in my prayers & those of countless Americans.'

During a White House press conference on Monday, Trump indicated that he had held off on calling out of respect for the grieving families

Sergeant Bryan C. Black, 35, Sergeant Jeremiah W Johnson, 39, and Sergeant Dustin M Wright, 29, were the other three killed in Niger

Trump on Tuesday called the families of the four US troops who were killed in Niger nearly two weeks ago.

It came a day after he said he would call them at the 'appropriate time' when questioned about his public silence.

'President Trump spoke to all four of the families of those who were killed in action in Niger,' White House press secretary Sarah Huckabee Sanders said in a statement late Tuesday.

'He offered condolences on behalf of a grateful nation and assured them their family's extraordinary sacrifice to the country will never be forgotten.'

Staff Sgt. Bryan Black, Staff Sgt. Jeremiah Johnson, Staff Sgt. Dustin Wright and Sgt. La David Johnson were all killed when militants thought to be affiliated with the Islamic State group ambushed them while they were patrolling in unarmored trucks with Niger troops.

Trump is said to have told Mrs Johnson that her 25-year-old husband 'knew what he signed up for... but when it happens it hurts anyway'

During a White House press conference on Monday, Trump indicated that he had held off on calling out of respect for the grieving families – then unloaded on former presidents with an inaccurate claim that his predecessors didn't call families of the fallen.

Scholarship set up for soldier's children The 5000 Role Models of Excellence Project – led by Rep. Frederica Wilson - has set up a scholarship for the children of Sgt. La David T. Johnson. A GoFundMe page set up said the money would go towards Johnson's three children's college funds and has already raised more than $390,000 in a day. He leaves behind a six-year-old daughter, a two-year-old son and an unborn child who is due in January. Advertisement

'So the traditional way if you look at president Obama and other presidents – most of them didn't' make calls,' Trump said.

'A lot of them didn't make calls. I like to call when it's appropriate, when I think I'm able to do it. They have made the ultimate sacrifice, so generally I would say that I like to call.'

When asked during the press conference to back up his claims about Obama, Trump appeared to try and backpedal.

'I don't know if he did. I was told that he didn't often. A lot of presidents don't, they write letters. I do a combination of both. Sometimes it's a very difficult thing to do but I do a combination of both,' he said.

Sgt Johnson is survived by his pregnant wife and their six-year-old daughter and two-year-old son

'President Obama I think probably did sometimes and maybe sometimes he didn't. I don't know that's what I was told,' Trump added.

Trump was heavily criticized for the comments by both Gold Star families and ex-staffers of former presidents.

Alyssa Mastromonaco, who served as a deputy chief of staff under Obama, was among those to immediately lash out at Trump.

'That's a f***ing lie,' she tweeted. 'To say President Obama (or past presidents) didn't call the family members of soldiers KIA - he's a deranged animal.'

Ben Rhodes, Obama's foreign policy advisor, said: 'This is an outrageous and disrespectful lie even by Trump standards.

A GoFundMe page has since been set up to help support the children of Sgt Johnson.

It has already raised more than $390,000 in one day.