THE deadline for the removal of UK Government conditions on Scotland’s Deposit Return Scheme (DRS) is due to expire as a Scottish Greens MSP warned the “scheme is on the brink”.

First Minister Humza Yousaf set out the timeline in a letter to the Prime Minister, saying a failure to revoke the conditions would put the scheme in “grave danger”.

Last week, UK ministers approved a partial exemption to the Internal Market Act for the DRS, but stipulated that glass could not be involved north of the Border.

It comes after we exclusively revealed calls for the UK Government to explain the reasoning behind its change in position on including glass in the scheme after the “striking coincidence” that a trade body had donated £20,000 to the Tories.

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A spokesperson for the Department for Environment, Food and Rural Affairs said accusations of ministers engaging in “sabotage” were completely untrue while Scottish Secretary Alister Jack dodged the question on BBC’s Sunday Show.

Speaking on Saturday, First Minister Humza Yousaf said: “I struggle to see it going ahead, and therefore the UK Government have a real choice here.

“They either agree to the full exemption, which is of course the regulations passed by the Scottish Parliament, or they’re in danger of sinking this scheme in its entirety.”

The deadline was set to allow for the Scottish Cabinet to discuss a response on Tuesday during its regular weekly meeting and provide an update to Holyrood.

However, the chance of the conditions being revoked seemed unlikely on Sunday, when Scottish Secretary Alister Jack said the Prime Minister should not back down.

Asked if the Government should reverse course, Jack said: “No – we’ve given the exclusion. There are four conditions in that exclusion which allow the scheme to work across the United Kingdom.”

If it goes live as planned in March, the scheme would see a 20p charge placed on drinks containers which would be refunded to consumers upon their return in a bid to increase recycling levels.

Scottish Greens environment spokesman Mark Ruskell MSP told BBC Radio Scotland’s Good Morning Scotland programme: “I think we are at a point now where the scheme is on the brink, there does need to be negotiation now around the detail of the UK Government’s letter and its conditions that it’s put down.

“Some of these conditions are very very challenging. If the UK Government continues to require the exclusion of glass then clearly that will have an economic impact on the viability of the scheme, it will also have a very damaging impact on the environmental benefits of the scheme as well.”

Asked whether the scheme could go ahead just with plastic, he replied: “I don’t know at this point and clearly there has been a lot of analysis and discussions with industry about the viability of the scheme, I’ve yet to see what the numbers look like on that.

“The exclusion of glass is very very damaging towards the scheme, it is not what was agreed back in 2019 between the UK Government and all the nations of the UK, it’s not the flexibility that was agreed and I think quite frankly the involvement of the Secretary of State for Scotland has been deeply unhelpful.”