Plaid Cymru is calling for this weekend's Six Nations match between Wales and Scotland to be postponed.
Party leader Adam Price said “all mass gatherings” should be “postponed or cancelled” with immediate effect.
Mr Price said the “safety” of vulnerable and at risk citizens should be “put before everything else”.
The Prime Minister is expected to announce later that the coronavirus outbreak can no longer be contained in the UK, signalling the start of the next phase in the battle against Covid-19.
Six Nations has been approached for comment.