The interview with Walter Kohl, the eldest son of former German Chancellor Helmut Kohl, appeared in the online edition of "ZEITmagazin" on Wednesday.

"For me," said Kohl, "Mrs. Merkel played a not-insignificant part in my mother's death."

Kohl's mother, Hannelore, committed suicide in 2001, less than two years after her husband - Chancellor Kohl - was involved in a scandal that revealed he had accepted a cash donation from unknown sources.

Merkel, then Christian Democrat (CDU) party general secretary, wrote a guest column in the "Frankfurt Allgemeine Zeitung" calling on Kohl to reveal more information about the payments. It was seen as the end of their amicable partnership. In the article, Merkel wrote that it was time for the CDU to "learn to stand on its feet" without Kohl, saying the chancellor's silence during the scandal "has done damage to the party."

"As an experienced politician, Mrs. Merkel knew she was starting an avalanche that would also damage our mother and our family," Walter Kohl said, adding that at no point did Merkel ask that Helmut Kohl's family be left out of the spotlight, despite knowing that Hannelore Kohl was quite sick with an allergy to light.

Merkel's rise to power

According to Walter Kohl, Merkel's behavior at the time was "sleazy," made worse by the fact that she and his mother had become friends.

Watch video 02:12 30 Years of Helmut Kohl

His mother "became persona non grata. For her it was even worse because she felt betrayed by Merkel."

Kohl added in the interview that his father "probably did a lot to escalate the donation affair," but that speaking about it now is more about "something much more fundamental: Angela Merkel's behavior in a party power struggle."

The affair eventually toppled Helmut Kohl from his role at the head of the CDU. He has never revealed where the money came from, despite heavy pressure, and the affair saw Merkel turn on her mentor and assume leadership of the party in 2000. Kohl insisted that breaking his silence would harm the party.

This was, according to Kohl, despite the fact that at the beginning of the scandal, Merkel had spoken within the party about protecting Helmut Kohl, and his family in particular, for all he had done for the party.

Estranged son

Walter Kohl and his brother have not spoken to their father for years, and a book written by Walter in 2011 revealed the struggles Walter faced living as the son of Germany's longest-serving chancellor.

In the interview with "ZEITmagazin," Walter Kohl said his father's visit in 2016 with Hungarian Prime Minister Viktor Orban, one of the most vocal Merkel critics outside of Germany for her refugee policy, was out of character.

"He's not who he was with the things he says today," Walter Kohl said. "The Helmut Kohl of old would never have given an autocrat like Orban such a friendly reception."

mz/msh