The tone in the Reform Party has deteriorated for months, with accusations coming out of Kaja Kallas' corner that couldn't be any clearer. In early January, for example, Kallas accused Pevkur of trying to ship her off to a less prominent voting district, trying to set himself up as the party's candidate in Harju County, where there are the most personal votes to be won.

On March 9, the party's leadership decided to dismiss its secretary-general, Tõnis Kõiv, replacing him with Kert Valdaru, a former public official hand-picked by Kallas. The move, explained to the outside with the need to give the designated chairwoman a chance to put her own team together, effectively sidelined Pevkur as chairman.

But simply replacing Kõiv wasn't enough: information was leaked that suggested he had bungled the party's finances, and that a close associate of Pevkur's at the Riigikogu had accessed party members' files without proper authorization.

Kallas' high-wire act likely to replace Pevkur with Laanet as deputy speaker

Over the last few days, word has been going around that the party also wants to replace Pevkur on the Board of the Riigikogu, where he replaced former Prime Minister Taavi Rõivas (Reform) after the latter got embroiled in a sexual harassment scandal in October last year.

On Sunday, Reform Party MP Kalle Laanet announced that he intends to succeed Pevkur. Kaja Kallas expressed her support of Laanet, calling him a "valuable candidate" in a message to fellow party members. In the same letter, she also said that Pevkur had asked her for her support, but that he wouldn't get it.

She couldn't side with anyone, she added, though she seems to think of Laanet as a reasonable choice: "In my opinion, Kalle Laanet is a valuable candidate who isn't hampered by personal grudges and could concentrate on the work of the Riigikogu's deputy president without spending time and energy on settling old scores," Kallas wrote.

Kallas also said that there are a number of people in the Reform Party's parliamentary group that don't support Pevkur and want to see him replaced as Second Deputy President of the Riigikogu. "That is why in my opinion the right way to go is to have a democratic vote, where the parliamentary group decides who to support," she added.

She was also vocal in her criticism of the party chairman and his standing with Reform's parliamentary group. Pevkur had had three years to win friends there, she wrote. "If you are really interested in the well-being of the party, and not just in holding a certain position, then it would be better to withdraw and let the parliamentary group support a third candidate nobody has an issue voting for," Kallas added.

Pevkur: Randjärv and Pentus-Rosimannus running smear campaign

Pevkur sent a message of his own to party members, pointing to MPs Laine Randjärv and Keit Pentus-Rosimannus and accusing them of again having started a campaign to undermine him and replace him with Kalle Laanet as deputy president of the Riigikogu. Pevkur also made it clear that he thinks Kallas is behind the move, and that Randjärv and Pentus-Rosimannus acted upon her request.

The personalities involved notwithstanding, what is currently happening has the potential to damage the party's reputation even further, only confirming the public impression that Reform's internal battles are still raging on, Pevkur hinted.

"The question is in the message we're sending out," Pevkur said. "Forcibly replacing a deputy speaker who is also the party chairman we're sending the message to the public that the infighting in the Reform Party continues. But nobody understands why we're doing it."

Various commentators meanwhile see the ongoing power struggle as an attempt of a group often referred to as Reform's "back room" to reassert itself. The group is usually placed in the political range of long-time party power broker Kristen Michal, who is generally seen as a key figure in Kallas' sudden rise in the party, and made up of key players of the Ansip and Rõivas years.