Manchester United has written to fans ahead of the club's final pre-season friendly on Tuesday against Valencia to inform them that using iPads or other tablets is prohibited.

The move comes ahead of the opening game of the Premier League season against Swansea next weekend, and is seen as a move to limit complaints by other fans who feel their views are restricted by those taking pictures or video of a game in progress.

An email sent to fans this week said it wanted to make people aware of the new regulations in time for the new season:

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"Supporters cannot bring large electronic devices (bigger than 150mm x 100mm) inside the stadium. For example, iPads or other tablet devices and laptops are now prohibited," the email said.

While large smartphone like the Samsung Galaxy S5 or HTC One (M8) are all still permitted under the new rules, larger 'phablet' devices like the Galaxy Note 3 from Samsung could be deemed to breach the new rules, as it has dimensions of 151 x 79mm.

Another reason believed to be behind the move to ban tablets is the fear of fans recording large sections of a game and posting them online, in breach of copyright rules.

The club goes on to say: "Also please be aware that large bags, large cameras and liquids (with the exception of a small bottle of water with the top removed) are included in our list of prohibited items."