Several of the world's biggest tea brands including PG Tips, Lipton, Tetley and Twinings have said they will work to improve the tea estates they buy from in India after a BBC investigation found dangerous, disgusting and degrading living and working conditions.

Harrods has stopped selling some tea products in response.

The joint investigation by Radio 4's File on Four and BBC News also found that some tea estates break the law by restricting public access to workers' living areas.

The BBC's South Asia correspondent, Justin Rowlatt encountered obstruction from management when he tried to access one particular estate.