BT should be forced to sell its broadband service which is causing millions of customers to suffer "dire" internet connection speeds, a report by MPs says.

The report says BT has "repeatedly failed to deliver" promised superfast services despite receiving £1.7bn of taxpayer subsidies. It recommends a radical overhaul including the sale of Openreach to encourage competition and improve quality.

Some 5.7m people, of which 3.5m are in rural areas, are not reaching the minimum speeds required by regulators whilst some experience "no service at all".

The research was published by former Cabinet minister Grant Shapps who said highlighted the effect of inadequate broadband on businesses.

BT workers were caught mocking the report when they failed to put the telephone down after calling the report's authors.

Mr Shapps posted a recording online of the answer machine message that he claims reveals the "contempt" the company shows for its customers.

The worker who makes the call is heard telling a colleague about the report.

"It's called Broadbad," he says.

The colleague replies: "Broadbad? Oh, that's clever. That's hilarious."

After discussing how the "n" of broadband has been crossed out, the first man says sarcastically: "Ooo, look at that."

Mr Shapps said the two men appeared "simply not to care" about the issues highlighted in the report about the poor services customers are enduring.