Speaking on ETV current affairs show Ringvaade, Siim Kallas declined to comment on his daughter's claim on Tuesday's Aktuaalne kaamera that Ratas would be ready to sell Estonia up the river if it meant clinging to power. He did, however, say that Ratas had disparaged Kaja Kallas.

Kaja Kallas' remarks sparked condemnation and calls for an apology from Centre Party members, including the prime minister.

"Opposition leader Kaja Kallas essentially accused me of being open to treason. This is a truly grave personal attack that requires [either] clear evidence or a public apology," Ratas said on Tuesday.

"I can't comment on this, but I understand what my daughter is saying," Siim Kallas said on Thursday's broadcast.

"This [also] does not take into account how much Jüri Ratas has mocked Kaja Kallas, and how she has been belittled by him in every way. Not much attention is paid to this. Kaja is sticking to her views and comments; everyone comments their own statements," he went on.

Siim Kallas also said that he didn't think the government was in crisis.

"I think the government is going to stay put right now," he said.

"It's getting harder and harder for them to deal with each other, but it will take time for there to be any serious confrontations. I have doubts about their actions, and I think we do so pretty strongly. This is how it seems to be going. There is no intrigue and no behind-the-scenes negotiations going on, since the government is simply staying put and there is no desire from any quarters to start casting around for something," he added.

Reform, co-founded by Siim Kallas, also celebrated its 25th anniversary on Thursday. Kallas said its two greatest achievements were in establishing the dominant financial culture in the country, and EU accession.

"I consider our best achievement to be a financial culture that has dominated Estonia for a very long time ... not talking about structural balances or other equilibrium, we are just talking about the fact that monetary matters must be in order. This is what we have cultivated, but it was not automatic - we still had to convince the people how budget matters work," he said, noting that Reform's "fingerprint" is ubiquitous in Estonian politics.

"Spiritually speaking, for me, one of the biggest highlights was when we joined the EU," Kallas noted. Estonian joined the EU in 2004. Holding a referendum on the matter was decided in December 2002, when Kallas was prime minister, and held the following April.

The original Ringvaade broadcast (in Estonian) is here.

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