Rhun ap Iorwerth was pressed over the state of the health service in Wales during his inaugural First Minister's Questions.
The new FM faced his colleagues in the Siambr on Tuesday to be questioned on the work achieved so far by the first-ever Plaid Cymru Welsh Government.
Mr ap Iorwerth clashed with opposition leader Dan Thomas, who reminded the First Minister that "Plaid Cymru only won 6% more than Reform" in the recent election.
He continued: "That very small lead can be eroded when you do not stick to your policies and when you do not show determination to put the people of Wales first. I'll just remind you of that."
In response, the First Minister said: "It's going to be a very long Senedd term if it starts in this way, that we got a certain percentage more than you in the election."

"Apologise to voters"
Opening his questions to the First Minister, Mr Thomas raised the number of people in Wales waiting more than two years to receive NHS treatment.
Reform's Welsh leader said: "Thousands of people in Wales are still waiting more than two years for treatment on the Welsh NHS, whereas in England two-year waits were virtually eradicated some time ago, which proves that ending two-year waits can be achieved."
"During the election campaign, you said that two-year waits could end in a matter of months, but your new health minister has said it will happen within four years."
Mr Thomas called on the First Minister to clarify what "expectations" the Plaid government has set for two year waiting lists, whether they are expected to end within months or within four years.
He pressed the First Minister to apologise to voters for "misleading them" should the answer be the latter.
In response, Mr ap Iorwerth emphasised his ambitions to both cut waiting lists and build a sustainable health service in the long term.
He said: "I reiterate that a priority for us now is to tackle, in the coming months, those issues of the longest two-year waits. In fact, I'm not waiting for the next months, work has already begun to put in practice the changes that are necessary to tackle that very issue."
"Social media"
The leader of the opposition continued with his focus on the NHS, suggesting that health should be the "top priority" for the Welsh Government.
He criticised Mr ap Iorwerth for highlighting international relations as within his remit as First Minister in a recent social media post.
Mr Thomas said: "On social media, you've highlighted the non-devolved matter of international relations as being within your remit as First Minister, an area that enjoys a £9 million budget."
"Reform believes that money should be spent here in Wales on the Welsh NHS. For example, it could be used to employ hundreds of newly-qualified nurses."
"So, First Minister, why are you continuing Labour's policy of spending large sums of money abroad when it should be spent in Wales and we should be putting the people of Wales first?"
In response, Mr ap Iorwerth said: "Let's be serious about the challenges that we face, rather than the small change that is referred to by the leader of the opposition."
"We are talking about significant sums of money that we are investing already through a budget deal last year into the NHS."
"But I can assure you of this: it's through innovation and it's through working with staff within the NHS that we provide that sustainability for the future."
The First Minister added: "I remind the leader of the opposition that he leads a group in Wales from a party whose leader does not believe in an NHS funded through general taxation."
"That is a principle that we will defend here as we deliver that NHS that's fit for the future, for patients and for staff alike."
"Unsatisfactory"
The First Minister was also questioned on what assessment he had made of accident and emergency performance in Newport and Islwyn.
Reform's Art Wright pressed the Plaid Cymru leader on whether he agreed the lack of a "full and properly functioning accident and emergency service" in Newport is having a "serious knock-on effect" on the wider communities.
The Casnewydd Islwyn MS said his constituents were facing longer journeys and increased waiting times with the hospitals facing growing pressure.
Acknowledging the need for "significant improvement on the current situation", the First Minister noted that the Grange Hospital in Cwmbran "consistently falls short" of meeting the four-hour standard.
He said: "Latest performance figures are unsatisfactory. Prolonged waiting times continue to pose significant challenges."
"I couldn't make it clearer than to say that my cabinet minister for health and care, and I, want to see much more being done to provide the kind of level of care that the member references."

Labour's Jayne Bryant drew on the work of the previous Welsh Labour government, claiming they had "invested significantly" in the Grange A&E because of "unacceptably long waits and corridor care".
Ms Bryant pressed the First Minister to share how the Welsh Government plans to fund the integration of pathways out of acute hospital care.
Recognising the importance of integration in creating a sustainable health and care service, Mr ap Iorwerth said: "What this government is determined to do is not just count the pennies but look at the outcomes that come out of investment, and that will guide us as a principle through the course of this government."

Welsh Conservatives spokesperson for health and social care - and MS for Casnewydd Islwyn - Natasha Asghar described the state of the health service as "one of, if not the most important issues that matter to residents across Wales".
Calling for the Welsh Government to engage with the Aneurin Bevan University Health Board and explore reopening the A&E at the Royal Gwent Hospital in Newport, she claimed it would "not only" reduce pressures on the Grange but also create significant job opportunities.
The First Minister responded: "We hear the calls, as I will hear calls, no doubt, for investment in different parts of the country."
"What's important to me, I think, is to recognise the challenges that are being faced by the member's constituents, to put together a level of service that provides for the needs of her constituents."
"Welsh Government officials, NHS performance and improvement, and the health board are currently working together to agree an intervention approach based on the infrastructure that we have for the delivery of health. Let's see where we can get on improving the services in that way."
Plaid Cymru's Peredur Owen Griffiths also commented referring to his experience of treatment in both the Royal Gwent and the Grange following recently tearing a tendon in his knee.
The Casnewydd Islwyn MS questioned whether the First Minister agreed that improving emergency care in the constituency requires "looking at the entire patient journey, not just the targets".
The First Minister responded: "Our plans to improve health services are based on a whole-systems approach, as the Member quite rightly noted."
"Our new workforce plan, for example, will include an emphasis on better strategic planning for services in order to facilitate patient flow, drawing on best practice already in place in some parts of Wales. "
"However, we need to extend that and embed it at a national level. We also know that the measures need to go hand in hand with strengthening community care, and I know that the Cabinet Secretary has a particular interest in ensuring that the importance of allied health professionals operates effectively and that that is reflected in our plans."


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