Uncertainty over the impact of Britain's future trade relationship with Europe on the supply of medicines is "an unwelcome distraction" for the NHS, the Health Minister Vaughan Gething has warned.
Talks between the UK Government and the European Union are in their final stages with the Prime Minister and the European Commission president due to hold more discussions later today.
There's still disagreement between the two and Boris Johnson has made it clear he is willing to end the talks if no further compromise is reached.
That would mean the UK would not have a free trade agreement with the EU when the transition period ends on December 31st.
Mr Gething said he remains concerned about possible disruption to the supply of medicines whether or not there's a deal or not.
He told the Welsh Government's regular press conference that the Chief Pharmaceutical Officers of Wales, England, Scotland and Northern Ireland have been working with each other and the pharmaceutical industry to try to spot potential shortages and come up with "alternative arrangements."
But he said "there is no getting away from the fact that disruption at our ports could disrupt supplies. That's why pharmaceutical companies themselves have looked at different ports of entry so they're not so reliant on Dover and Folkestone, and they've taken that into their own hands."
And he warned that any disruption could last for a longer period, saying that "the disruptions into supply may not be there on day one, but there's a challenge about longer-term arrangements, and that's still to be worked through."
"The unavoidable truth is in the broader arrangements, we still don't know where we're going to be."
"That uncertainty is really unhelpful when it comes to some of the medication that we know that we need to have and cannot possibly be held up in our ports because otherwise, it would lose its effectiveness."
Paymaster General Penny Mordaunt told MPs this afternoon that the UK Government is planning to ensure that the supply of medicines is not delayed by any disruption at the ports.
She said: "The supply of medicines and medical devices, even without the pandemic, has always been a priority right back to last year and the potential no-deal scenario planning that went on."
"We take this very seriously indeed."
Those medicines include the COVID vaccine and the UK Government has made arrangements to fly them in if there's disruption at British ports.
The Health Minister said he continues to hope there'll be "a breakthrough" and a deal agreed.
"It's a hugely unwelcome distraction to winter in the National Health Service in normal times let alone a winter where coronavirus is very much with us in every community in Wales and causing harm as it goes along."