Controversial plans by the Welsh government to introduce a compulsory Covid pass for nightclubs and big sporting events will go ahead after the Senedd backed the scheme by the narrowest of margins.

The Labour-led government argued that the pass, due to come into force on Monday, was needed to drive down worrying rates of Covid-19 infection especially among young people in Wales.

They claimed the scheme would ease pressure on the NHS and help keep premises such as clubs open this winter. They accused those who opposed it of “gross irresponsibility”.

On Tuesday evening the Tories, Plaid Cymru, and the Liberal Democrats, all voted against the move but the plan squeezed through by 28 votes to 27.

Announcing the pass last month, the first minister of Wales, Mark Drakeford, said he was determined to take stronger, earlier, action than the UK government in England, claiming measures that were part of Boris Johnson’s “plan B”, such as a Covid pass and working from home, were in his “plan A”.

Drakeford rejected the idea that the scheme was a vaccination passport in all but name, pointing out that it would be possible to get the Welsh pass by taking a lateral flow test.

A crowd of a few hundred people, some protesting against the scheme – and some anti-vaxxers – gathered outside the Senedd, on Cardiff Bay, ahead of the debate.

The health minister, Eluned Morgan, said Covid cases were increasing across Wales, especially among young people, with rates for under 25s about 1,000 per 100,000 people. Morgan said these were the people most likely to go to venues such as nightclubs. She said keeping such venues open had not been an easy decision in the light of such high Covid rates. “We are facing some of the highest rates we have seen since the start of the pandemic. We have to do something to stop the turbo charging.”

Morgan said pressure on hospitals was rising steadily. “There is a need to take early action to avoid longer term harms. The scientists are telling us to act early, act now. Every day we hesitate those rates go up and we will put more pressure on the NHS. Not supporting this measure will be an act of gross irresponsibility.”

Russell George, the Welsh Conservative shadow health minister,argued that introducing a vaccine “passport” would lead to Wales becoming a checkpoint society.

Rhun ap Iorwerth, the health and social care spokesperson for Plaid Cymru, said it was not clear how police could check whether people were falsifying lateral flow tests and worried that it could be a disincentive for young people to be vaccinated.

The Liberal Democrat Jane Dodds said she believed Covid passports were an “infringement on freedom and liberty”, and added that the National Autistic Society had raised concerns with her.

The Night Time Industries Association, which represents 100 venues in Wales, said the passes represented “a significant barrier” for its operations. It argued that operators could not afford the extra resources and logistical challenges that a Covid pass would create.