Speaking to journalists at a hastily-convened press conference, Vejonis said he supported the formation of a Saeima investigative committee to look into the matter, and invited members of parliament to cooperate with it.
"I'm in favor of the rule of law, a strong society and an independent media," he told a sparsely-attended press conference.
"There must be further analysis of the content of the conversations," he said, suggesting that anti-corruption force KNAB should make that content available "as quickly as possible."
"Everyone involved [in the oligarch conversations] should explain and take responsibility for their actions," he added.
But he notably stopped short of demanding any specific measures or the resignation of any of the ministers, mayors and other public servants implicated in the conversations. There was no talk of legal action and the statement amounted to little more than an appeal to those implicated in the conversations to explain themselves - which they have thus far shown very little interest in doing.
The move came after a meeting of the National Security Council at which the ramifications of the so-called 'oligarch conversations' involving a trio of Latvia's most notorious politician-cum-businessmen and their associates discussed parcelling up power and profits between themselves.
The National Security Council would revisit the topic at its next meeting, he said.
Journalists were give just 45 minutes to assemble at Riga castle for a briefing, raising hopes that a dramatic development was about to take place.
However, in the event Vejonis' statement was vague, not even mentioning the oligarchs by name, and journalists themselves failed to cover themselves in glory by not asking even a single question at the end of his speech.