Chinese “kill switches” have been found hidden in American solar farms, prompting calls for Ed Miliband to halt the rollout of renewables.

On Thursday, the Energy Secretary was urged to impose an “immediate pause” on his green energy blitz to review whether UK solar plants are also at risk.

The components found in the US included cellular radios capable of switching off the equipment remotely, raising serious concerns about grid security, according to Reuters.

They were found inside power inverters manufactured by unnamed Chinese companies.

Power inverters are the key links between solar or wind farms and the rest of the power system, converting their electricity so the wider grid can use it.

One source told Reuters that compromising such equipment would give Beijing the ability to inflict blackouts on the West, claiming it would create “a built-in way to physically destroy the grid”.