Plaid Cymru MS Mabon ap Gwynfor has said that Welsh Labour supporters are "losing patience" with the party because of its "blind support of the Union."
The MS for Dwyfor Meirionnydd also said that Welsh Labour supporters are "way ahead of their party in supporting Indy".
The comments were made in the context of the First Minister's opposition to the devolution of welfare powers.
Universal Credit was increased by £20 a week at the start of the pandemic, however this increase is due to come to an end in September.
Mr. ap Gwynfor said: "The First Minister complains UK Gov are about to take £20/week Universal Credit away from most deprived, yet opposes devolving welfare.
Lab. supporters are way ahead of their party in supporting Indy, and are losing patience with Lab because of their blind support of the Union."