Ed Miliband is being urged to block Elon Musk's bid to supply electricity to British homes due to national security concerns.
Mr Musk's company Tesla has applied for a licence to provide power to homes and businesses in England, Scotland and Wales as soon as next year.
But there have been objections to Tesla's application to energy regulator Ofgem due to Mr Musk's controversial political activity.
The billionaire has been a strong ally of US President Donald Trump, while he has also publicly voiced support for far-right activist Tommy Robinson.
In a letter to Mr Miliband, the energy secretary, the Liberal Democrat leader Sir Ed Davey has warned against allowing Tesla to become an electricity supplier in the UK.
