Nearly a quarter of homes and businesses in the UK are getting broadband speeds of less than 10Mbps, new figures have revealed.
According to Ofcom data analysed by the House of Commons library, just 24 per cent of people receive speeds that meet the government's basic standard.
The problem was found to be particularly acute in rural areas, with broadband speeds about half as fast as those in major towns and cities.
However, city centres were also found to have especially low speeds, when compared with suburban locations close by.
London was identified as one city where this is the case, along with Birmingham, Nottingham, Leeds and Glasgow.
The findings come after the government confirmed that universal high-speed broadband is to be delivered by a regulatory Universal Service Obligation (USO), the government has confirmed.
The decision means that everyone in Britain will have the legal right to request minimum speeds of 10Mbps by 2020.
According to the government, this is the speed that will meet the typical needs of a family that wants to browse the web, stream films and carry out video conferencing at the same time.
Responding to the figures, a Department for Culture, Media and Sport spokesman told the Telegraph: "Around 98 per cent of UK homes and businesses can now get speeds of 10Mbps or faster, so we'd encourage those with slow connections to check with their provider whether a faster connection is already available.
"But we want to make sure no-one is left behind, which is why we are making reliable, affordable, high-speed broadband a legal right for everyone by 2020."
Grant Shapps, Head of the British Infrastructure Group of MPs, added that it is "not good enough to simply claim that people aren't taking up faster speeds where they are available", as they are prohibitively expensive for some.
As a result, he believes the government has "a responsibility to do more to get people on to better broadband".
Kingston upon Hull East was found to be the location with the worst broadband in England, as one in three households in this area are unable to receive speeds of more than 10Mbps.
Slow broadband connectivity was also found to be a widespread issue in rural parts of Scotland, Wales, Yorkshire and the south-west.