CNN  — 

When a bipartisan group of lawmakers visited the Ukraine border in March, an unexpected guest showed up on the trip: GOP Rep. Victoria Spartz of Indiana.

Spartz, the first Ukrainian-born member of the US Congress and an outspoken advocate for her home country, had expressed interest in joining the congressional delegation but wasn’t invited to attend the trip, which consisted primarily of House Foreign Affairs Committee members, a panel where Spartz is not a member.

So, she used her own funds to fly to the border of Ukraine in Poland and linked up with lawmakers once there to join in on some of their meetings, according to multiple sources familiar with the situation.

Her surprise appearance, the circumstances of which have not been previously reported, was initially viewed as a welcome addition – albeit an unusual one – as lawmakers sought to rally Western support for Ukraine amid Russia’s bloody assault on the country that began a week earlier.

But members who were part of the official trip told CNN that Spartz was “argumentative,” “accusatory,” and “unhelpful” during key meetings with NATO members, generals and government officials, sparking concern that her presence was doing more harm than good.

“She crashed our CoDel. She was like a bull in a china shop,” said one GOP lawmaker, who like other members for this story was granted anonymity to speak more freely about a colleague and due to the sensitive nature of the subject. “I don’t know if it was pent-up frustration or she didn’t feel like she was getting enough proper information, but she was just accusatory and rude.”

Spartz, in an email to CNN, pushed back on the anonymous criticism of her decision to elbow her way into the congressional delegation and refuted the description of her behavior on the trip.

“This accusation is a cowardly misrepresentation of facts by some jealous members or staff since we had a very productive bipartisan CODEL in March,” Spartz said. “I did not come to Congress to get paid for my travel vacations or dinners, but rather get things done. I have always been willing to spend my own hard-earned money to help with causes I care about.”

That bipartisan frustration over Spartz’s behavior was only the beginning. In the nearly six months since the war began, Spartz has publicly criticized the Ukraine government, peddled corruption allegations against the Ukrainian government and some of Ukrainian President Volodymyr Zelensky’s top aides, and spurred complaints from her colleagues that she is mirroring pro-Russia talking points.

“President Zelensky has to stop playing politics and theater, and start governing to better support his military and local governments,” Spartz said in a press release last month, in one example of her outspoken criticisms of Kyiv.

Spartz, a 43-year-old businesswoman, has repeatedly insisted, publicly and privately, that she wants Ukraine to win, and that she is only attacking Kyiv because she wants to help remove any potential obstacles to a Ukrainian victory over Russia. She says she has visited Ukraine six times since th