A cross-party group of MPs is calling for a ban on the export of plastic waste over concerns the UK is passing the buck to the world’s poorest people to clean up its rubbish.

MPs have tabled an early day motion to highlight growing concerns first raised by the National Audit Office that millions of tonnes of plastic waste sent abroad for recycling may be being dumped in landfill.

The EDM is sponsored by the Liberal Democrat MP Tom Brake, Green party MP Caroline Lucas, Labour MPs Geraint Davies and Mike Hill, Plaid Cymru’s Ben Lake, and Kelvin Hopkins, an independent MP.

The plastic recycling system in the UK has been in the spotlight since China banned imports of plastic and other waste from the west over concerns about the quality of the material.

It was followed by Malaysia – which imported 105,000 tonnes of plastic for processing last year – imposing restrictions, and then Thailand and Vietnam, leaving the plastic recycling export market in crisis.

Two-thirds of UK plastic waste is exported for recycling in an industry worth £50m last year, rather than being processed and used in the UK. The Guardian revealed recently that the export market was under investigation over suspected abuses.

The MPs said many of the countries in the global south receiving the UK’s rubbish had high levels of plastic waste mismanagement and they were extremely concerned that the sight of piles of plastic rubbish generated in the UK was increasingly common across the global south.

“This house … strongly condemns the practice of leaving some of the world’s poorest people to deal with the UK’s plastic waste … The government should not pass the buck to the global south on plastic, instead dealing with our own waste on UK soil,” the motion read.

The MPs said they were backing a campaign by A Plastic Planet for a complete ban on plastic waste exports to the developing world.

Businesses in the UK have long complained that they are disadvantaged when it comes to processing plastic waste in the UK. They have called for more investment into processing plants in the UK and an end to the incentives to export plastic to be recycled.

But Simon Ellin, chief executive of the Recycling Association, warned that banning exports could backfire. He said it would mean more plastic ending up in landfill in the UK.

“Most of our plastic exports take place in a compliant manner,” said Ellin. “If we were to ban the legitimate trade in recycled plastics, then it will decimate our industry, prices will crash and material will end up in landfill … We should definitely look to invest in our own plastic reprocessing infrastructure in the UK, but exports should have their place too as part of a global economy.”