Plaid Cymru say Covid 19 deaths should have been a 'wake up call'.
Plaid Cymru say the delay of introducing Covid 19 tests into all care homes across Wales should be the subject of a future inquiry.
Yesterday, Health Minister Vaughan Gething said testing would be extended this coming week.
Until now, only people who were in homes where there'd been a confirmed case of the virus were tested.
Shadow Minister for Local Government Delyth Jewell says coronavirus deaths in care homes should have been a 'wake up call' to introduce testing for all sooner.
She said: "This is a long awaited recognition of what we have consistently argued for.
"The tragic cases of Covid-19 in care homes and its prevalence within them should have been a wake-up call for the Welsh Government that testing everyone was a necessary life-saving step.
"The refusal to do so up to now should be the subject of examination in the future inquiry.
"While it is a welcome change of approach, Ministers must now publish the advice which informed the previous policy of not testing in every care home and how it has now changed".