New Democrat MP Christine Moore says she can disprove a former soldier's claim that she engaged in an "inappropriate" relationship with him in 2013.

"I have done nothing but cry [since the story came out.] It's terrible to see how someone can want to tell so many lies and I really don't know for what reason he's doing this," she said in French during a media conference in her riding of Abitibi-Temiscamingue Monday.

"It's so mean as an attack."

Veteran Glen Kirkland told CBC News that Moore approached him after he testified about the treatment of injured soldiers in Afghanistan before a parliamentary committee in June 2013.

He has alleged she led him to her office, where she gave him alcohol, then returned to his hotel and later sent him explicit messages.

Kirkland alleged Moore, a nurse, offered him gin even after he said he had told her he was taking medication and was not supposed to be drinking.

"Look, I'm not crying rape," Kirkland said. "I don't like to think of myself as a survivor. I prefer 'thriver.' But what she did was inappropriate. Was I a willing participant? I guess it depends on your definition of willing. There was a power imbalance. There was a level of authority there."

Moore said that, after their testimony, she invited Kirkland and other veterans for a drink in her office, adding the door was kept open and staff were on hand. She said she doesn't remember what liquor she had on hand, but that she doesn't drink gin.

She said the gathering moved to a patio on Ottawa's Sparks Street while she attended an event in Parliament's East Block at 6:30 p.m. Eventually, she said, she met up again with the veterans, along with some staff.

NDP MP Christine Moore, centre, poses with veteran Glen Kirkland, right, and Matthew Luloff, a Liberal staffer, in a photo shared with reporters by Moore. Moore said she met up with Kirkland and others on a Sparks Street patio following his committee testimony in June, 2013. (Christine Moore photo)

Moore said Kirkland followed her back to her office and kissed her, and she responded to the kiss. She said he asked her if she wanted to take her clothes off and she said no, that she didn't think there was time because she had to return to the House of Commons for votes and was also afraid of staff members catching them.

She said Kirkland sent her a text inviting her to his hotel and she joined him after voting; she described what followed as a consensual sexual encounter.

Moore says she dated Kirkland for 4 months

Moore said she and Kirkland had a romantic relationship for four months, but she ended it due to the long distance involved. She added that Kirkland was going through a difficult divorce at the time.

At her press conference on Monday, Moore showed reporters photos of her and Kirkland and an email containing a plane ticket and flight itinerary indicating Kirkland planned to visit her in Quebec, citing both as proof of the relationship.

Kirkland, now a realtor in Manitoba, has insisted that they were never in a relationship and alleged Moore once showed up to his home in Brandon, Man., uninvited.

"She said that we were in a relationship which is just completely false. [Meeting up] three times over, like, nine months - I have a better relationship with my dentist. It's just not a thing. It's completely inaccurate," Kirkland told CBC News Network's Power & Politics host Vassy Kapelos Monday.

For a story last week, CBC News sent a list of questions to Moore that went unanswered at the time. After the story appeared, NDP Leader Jagmeet Singh suspended Moore from all her duties pending the completion of a third-party investigation.

In a statement today, Singh said: "There are clear discrepancies between the accounts of Mr. Kirkland and Ms. Moore, and that is why it is so important to have a balanced and unbiased investigation into the allegations made."

"The process of selecting a qualified investigator, who can proceed in a timely manner, is already underway and should be completed in short order. I trust both parties will participate with the investigator in good faith," Singh said in the statement.

Moore said Singh had no choice but to call an investigation given the extent of the allegations.

Moore told reporters she intends to bring a defamation lawsuit against Kirkland, as well as columnists Neil Macdonald from CBC News, Christie Blatchford from the National Post and Rosie DiManno from the Toronto Star, who reported on the matter.

Earlier this year, Moore sent a letter complaining about her caucus colleague Erin Weir's behaviour, prompting an investigation that turned up sexual harassment complaints against him.

Weir has since been kicked out of caucus.

The party said Weir did not own up to his behaviour, while Weir blames his expulsion on the fact that he spoke out about the case publicly.