STR/NurPhoto via Getty Ukrainian President Volodymyr Zelenskyy and former spokesperson Iuliia Mendel
When Iuliia Mendel first met her future boss, Ukrainian President Volodymyr Zelenskyy, for an interview to become his press secretary, she didn't expect him to be dressed casually in jeans and a T-shirt. Or that he would so thoroughly appraise her "on a psychological level."
"He looked me in the eye throughout the interview," she tells PEOPLE. "He wanted to assess from the start that he was seeing the real me."
"He asked me why he should hire me, and I said: 'If a man from a poor background from some small province in Ukraine can become the democratic president of the country, then a girl like me from a poor background in another province can become press secretary to the president,'" she adds.
Mendel, 36, won the top post in a field of 4,000 applicants and went on to work with him for two years in the run up to the war.
In the position, she quickly discovered that her new boss was a health nut. "He is addicted to fitness! That was evident from the first day I started working with him. We flew to Brussels and he had a phone conference with journalists which he took from the gym on his training bike."
"The interview wasn't planned — but the gym was — so he decided to combine the two."
Mendel says that Zelenskyy, 44, always starts his day either by jogging or going to the gym — even in a war zone. "Wherever we went, even it was the [contested region of] Donbas, he always went out running," she says.
The president set up a national fitness program that he promoted on his Instagram account called #HealthyUkraine.
Unlike Zelenskyy, Mendel often came under attack in the media for the way she looked and dressed. "In my country there are many demands about women and the way they look, and this means a female has to be 100 percent perfect in every way."
A year after taking up her post, rumors began circulating that she was having an affair with the world leader and was pregnant with his child. She dismisses the gossip, calling it fake news spread by Russia to discredit the Ukrainian president, who has been happily married to his high school sweetheart, Olena Zelenska, for 19 years. The couple have two children.
"Nobody could prove anything," she tells PEOPLE. "I didn't discuss it (with him) because it was so ridiculous. We had a professional relationship."
She adds: "It wasn't an attack on me, it was an attack on the first couple of Ukraine."
Yulii Zozulia/ Ukrinform/Future Publishing via Getty
Zelenskyy reacted to the rumors with what Mendel says is typical humor, making a joke about her supposed "condition": "It was during a very important meeting in his office just after the news first came out. He smiled across at me and said: 'How are you feeling?' Everyone around the room chuckled. He wanted to break the ice."
Zelenska, who was rumored in the media to have been hospitalized by the shock of the so-called revelation, didn't mention it to Mendel. "She of course never raised the topic. It's ridiculous," Mendel says. "It just shows the power of Russian propaganda, because it was a big scandal."
Another scandal broke after she physically pushed journalists away from her boss. The incident hit the headlines and calls were made for her resignation.
"But the next day, at a press conference, he turned to me smiling and said: 'You didn't push anyone, did you Yul?' He uses his humor as a political tool to put people at their ease," she says.
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Zelenskyy is now viewed on the world stage as a steely warrior-leader. But he first rose to fame in his home country as an actor, playing the role of a simple man who becomes president of Ukraine in the TV comedy Servant of the People. He named his political party after the top-rating show before running for office.
Talking about the series, which ran for four years, Mendel says "it was great PR."
"People had been watching him and they loved him because he was the King of Humor in Ukraine." But as she points out, "it is a very different thing to play the role of a president in front of the cameras and to actually work as a president."
She tells PEOPLE he can be deadly serious when required, recalling how taken aback Russian President Vladimir Putin was by Zelenskyy's persistence during their first round of negotiations in Paris in 2019.
"Putin kept looking around to his advisors saying, 'We need to double check on that.' I could see his confidence was rather shaken. But Zelenskyy would never give up. He'd say: 'I don't think you understand what I'm saying here.'"
olenazelenska_official/Instagram Ukrainian President Volodymyr Zelensky, wife Olena Zelenska and their two children
The two leaders have very different values, Mendel adds. "Putin promotes so-called traditional family values, but he himself is divorced and there are a lot of reports of him having different women. Zelenskyy doesn't have to promote his family values. He is very proud of Olena. He listens to her advice."
Mendel resigned from the post before her book, The Fight of our Lives, was published in Ukraine last year.
"I told [Zelenskyy] that I was publishing the book," she says. His reaction? "He didn't want to read it or see it or contribute. And he didn't ask what I was writing. But when I left office he wished me good luck."
The Fight of our Lives will be released in English on Sept. 13.
The Russian attack on Ukraine is an evolving story, with information changing quickly. Follow PEOPLE's complete coverage of the war here, including stories from citizens on the ground and ways to help.