The sale of plastic straws, cutlery and polystyrene cups and food boxes is to be banned in Scotland next year as part of measures to reduce waste and pollution.

The Scottish government said the ban would cover all single-use polystyrene food containers and their lids, as well as plastic stirrers, balloon sticks, plates and coffee stirrers, and would come into force on 1 June.

The measures parallel similar bans in force or planned around the UK, and it expected to lead to a boom in compostable and paper-based packaging. However, there are doubts about how effective it will be.

Single-use plastic straws, cotton buds and drink stirrers were banned in England in 2020. The UK government is consulting on banning single-use plates, cutlery and polystyrene food packaging for England in several years’ time, but no target date has been given.

Because of the delay, Scottish ministers fear their measures could be undermined by the UK government’s internal market rules, which are intended to harmonise the movement and sale of goods within Britain post-Brexit.

Lorna Slater, a Scottish Green party minister, said that because there was no similar action in England, Scotland’s ban could be sidestepped by people buying or moving single-use plastics from England. Slater is writing to ministers in Westminster to see whether the UK-wide measures would be changed to ensure Scotland is able to enforce its policies.

The internal trade rules have already forced the Welsh government to delay its plans to ban single-use plastics, first announced last year, because of the extent of cross-border travel, trading and recreation with England.

Cardiff is now planning to charge for single-use plastic items until UK ministers clarify the internal market rules.

Although charges for plastic bags and a ban on microplastic in washing products are in force UK-wide, and a new tax on plastic packaging will be introduced next year,, anti-waste campaigners say all four of the UK’s governments are taking“snail’s pace” action on single-use plastics. The EU banned single-use plastics in July across all 27 member states.

It is estimated the average person uses 18 throwaway plastic plates and 37 single-use knives, forks and spoons each year. A study last year found businesses and consumers in the UK and US produced more plastic waste per head than any other major economies.

“Every year, hundreds of millions of pieces of single-use plastic are wasted in this country,” Slater said. “They litter our coasts, pollute our oceans and contribute to the climate emergency. That has to end and this ban will be another step forward in the fight against plastic waste and throwaway culture.”