Rhun ap Iorwerth, who attended a pro-independence march at the weekend, distanced himself from reported remarks by the Russian foreign minister Sergei Lavrov, who questioned whether the UK has a future.

Welsh Conservative Senedd leader Darren Millar said Lavrov's comments showed the "folly" of focusing on "constitutional navel gazing".

Speaking in the Senedd on Tuesday, the first minister questioned the "wisdom" of senior Welsh politicians "quoting a Kremlin propagandist in order to pursue their unionist agenda here".

Ap Iorwerth has called for the powers to call such a vote to be devolved, and has said he would make the case for Wales to be an independent state.

During the Senedd election campaign in May, Plaid said the vote was not about independence.

Plaid has ruled out trying to hold a referendum in this Senedd term, which ends in 2030, and has not put a date on when one could happen.

However, two weeks ago he called a summit of the leaders of Sinn Féin and the SNP, where the three parties said Westminster's time "is coming to an end".

The nationalist leaders from Plaid Cymru, Sinn Féin and the SNP - who want their countries to leave the United Kingdom - signed an agreement on Monday which said no Westminster government had the right to "block democracy".

Sergei Lavrov appeared to seize on the summit in comments at a youth conference where he said he did "not know what will become of the country called Great Britain", according to The Times.

During first minister's questions, Millar asked if ap Iorwerth was "pleased to have Putin's Russia cheerleading on this independence mission that you've set yourself on".

He questioned whether the first minister had realised "the folly of focusing on that issue" rather than "cracking on with improving our sliding educational standards, getting to grips with the crisis in our NHS, and trying to fire up the Welsh economy".

In response, the first minister said: "Wales's constitutional future is a matter for the people of Wales.

"It isn't for the Kremlin to endorse, to oppose, or to exploit."

But he said Millar, and the Labour Secretary of State for Wales Stephen Kinnock, who he said was "on the same page", "may wish to reflect wisdom of quoting a Kremlin propagandist in order to pursue their unionist agenda here".

He said he had visited Kyiv with Millar, because "we believe in the right of the self-determination of the people of Ukraine. It so happens that I also believe in the right of the self-determination of the people of Wales."

Millar went on to accuse ap Iorwerth of doing "everything to make this Senedd about the issue of independence" since the election.

"You either clearly didn't get the memo that you wrote yourself," he said.

To laughing from his backbenchers, ap Iorwerth replied: "I feel as if there's an attempt every week to draw a big rabbit out of a hat that the leader of Plaid Cymru believes in independence for Wales. That doesn't come as a surprise."

Reform's Welsh leader Helen Jenner asked how an independent Wales would defend itself.

"In Wales, we are proud to play our part in the defence of the United Kingdom. This brings us greater national security and high-quality, high-skill jobs," she said.

Ap Iorwerth said: "My attitude will always be to seek ways of working together internationally to strengthen the way that we can step up to the threats that we face, not least from Russia, with the aggression shown towards our European partners, Ukraine."

Later, Ken Skates, Welsh Labour leader, asked if ap Iorwerth had not briefings "from intelligence chiefs in the UK defence forces over the specific scale and breadth of threats facing Wales and its people".

Ap Iorwerth said: "I do indeed receive briefings when it comes to matters that are of concern in terms of the resilience of Wales. I have spoken here on a number of occasions about the way I have approached the whole question of resilience."