The UK’s communications watchdog has called for a probe into Microsoft and Amazon’s dominance of the country’s cloud computing market in the latest challenge to the tech giants from global regulators.

Ofcom said on Wednesday it was “particularly concerned” by the practices of Amazon Web Services and Microsoft, which together control between 60 and 70 per cent of the UK cloud market. It has proposed referring the sector to the Competition and Markets Authority for further investigation.

Cloud computing is dominated by Amazon and Microsoft, and has become a crucial driver of revenue at the tech giants.