Measures that would have blocked companies found to have used forced labour in any part of the state-owned Great British Energy supply chain from receiving public money could be overturned this week.
Labour MPs are being whipped on Tuesday to throw out the clause that was inserted into the energy bill in the House of Lords in February.
But the Labour MP Alex Sobel is proposing to buttress the measure by moving an amendment to the bill that would authorise the independent anti-slavery commissioner to determine whether the threshold of credible evidence has been met.
The move has the support of the anti-slavery commissioner Eleanor Lyons, but is raising concerns in the Foreign Office, which is intent on rebuilding relations with China. The chancellor, Rachel Reeves, and the foreign secretary, David Lammy, have visited China since taking office.
Concern has long been expressed that Chinese-manufactured solar panels likely to be bought by Great British Energy are made using Uyghur slave labour, a charge the Chinese government rejects. China dominates the solar panel market.
Labour ministers say Great British Energy will already be empowered, and indeed be required, by law to root out slavery anywhere in its supply chain.
Ministers also say a pre-existing solar taskforce co-chaired by Ed Miliband, the energy secretary, is charged with addressing the issue. But Lyons said: “A decade ago the UK led the way setting new standards in the fight against modern slavery. Today we have fallen behind.”
The business and trade select committee warned recently the UK is at serious risk of becoming a dumping ground for products made with forced labour: “It is well evidenced that the renewable sector is heavily dependent on companies sourcing from areas like Xinjiang in China, and that forced labour is endemic in the region through involuntary labour transfer schemes. The Great British Energy Bill provides an ideal vehicle to ensure that the green transition is not built on the back of contemporary slaves.”
Sobel said: “The UK has been crystal clear that the UK will not tolerate slave-made goods and appreciates more must be done to root them out. Great British Energy provides us with the opportunity to not only pursue our green transition but bolster our national security, but only if we are to reduce our dependence on China.
“Ensuring our solar supply chains are free from slavery would also see the UK take a leading position on human rights, as a force for good.
“We have listened to the government arguments and tabled an amendment which would provide a practical solution to this issue, assuring we are aligned with actions in Europe and the US.”
The amendment passed by 177 votes to 127 in the Lords and has Conservative support, as well as the backing of the human rights barrister Helena Kennedy.
Lord Offord, a former Conservative exports minister, said: “The UK’s Modern Slavery Act 2015 requires companies to take responsibility for their supply chains, yet we know that modern slavery remains a serious issue in the global energy sector, particularly in the sourcing of solar panels, batteries and raw materials such as lithium and cobalt.
“This amendment does not create unnecessary bureaucracy or hinder investment; it simply ensures that taxpayers’ money does not fund exploitation.”
In opposition Labour backed moves to declare China’s actions in Xinjiang genocide and to block trade deals with countries found by UK courts to have committed genocide.
But in a speech last week Lammy said he had asked the Foreign Office “to turbo-charge the relationships which will generate the greatest returns on investment for UK plc in the medium-term. At the top of that list stands the EU, China and the United States of America”.
He called for pragmatic engagement with China, cooperating on climate change goals without endangering UK national security. He said future ambassadors “will in priority markets be assessed against their delivery of trade and investment wins overseas”.
