Nearly 300,000 attempts were made to access porn websites from computers within the Houses of Parliament over the past year, official records have shown.

The figure - which represents more than 800 attempts per day - was released by Palace of Westminster IT chiefs in response to a request under a Freedom of Information request from the Huffington Post UK website.

It covers devices linked to the parliamentary network, including those used by MPs and peers, their staff and other employees.

Officials sought to play down the significance of the total, insisting it was inflated by pop-ups, auto-refresh and other web design features and did not reflect deliberate efforts to access sexual content.

They are also investigating the reason for wide variations between the monthly figures - with as many as 114,844 last November but just 15 in February 2013.

"We do not consider the data to provide an accurate representation of the number of purposeful requests made by network users due to the variety of ways in which websites can be designed to act, react and interact and due to the potential operation of third party software," a House of Commons spokeswoman said.

Visits to otherwise blocked adult sites "may nevertheless be recorded in this dataset depending on website design", she added.