Ofcom has fined two companies a total of £40,000 for making more than 43,000 abandoned and silent calls.

Separate investigations into Green Deal Savings Limited, a company offering home energy efficiency services, and MYIML Limited, a lead generation company selling renewable energy deals, found both had persistently misused telephone networks.

Telecoms regulator Ofcom has set a limit on the number of abandoned calls that organisations can make and also says such calls must include a recorded message with information about the caller and how households can opt out.

Its policy on persistent misuse states that abandoned calls should not account for more than three per cent of live calls over each 24-hour period.

However, Ofcom says MYIML breached this threshold, making an estimated 30,296 abandoned calls between 16 December 2013 and 3 February 2014 (see MoneySavingExpert.com's No Cold Callers guide for help stopping spam calls, texts and post).

The company also failed to include a suitable phone number in the recorded message that consumers could call to decline future marketing calls.

Green Deal Savings, meanwhile, failed to ensure an information message was played in the event of an abandoned call and made an estimated 12,703 silent calls between 27 October and 14 December 2013.

It also made approximately 420 abandoned calls in one 24-hour period on 27 October last year.

Ofcom says it has fined each company £20,000, which will be passed on to the Treasury.

'Committed to tackling this issue'

Ofcom's consumer and content group director Claudio Pollack says: "We know that silent and abandoned calls can cause consumers annoyance, nuisance and distress.

"These latest fines help demonstrate to organisations that there are consequences for operating outside of the law.

"We're committed to making full use of our powers to tackle this issue and reduce consumer harm from nuisance calls."

What are silent and abandoned calls?

Abandoned calls can occur when automated calling systems, used by organisations to maximise the time agents spend talking to consumers, dial too many numbers and there are not enough employees to handle the calls.

A silent call is where the phone rings but there is only silence when the person answers it and no information message is played.