Britain will be required to inform Mauritius about military attacks launched from the Chagos Islands under Sir Keir Starmer's controversial £30billion deal, it has emerged.

The agreement, which transfers sovereignty of the islands to Mauritius, has sparked outrage among MPs and former military chiefs who warn it could compromise national security.

Critics have described the arrangement as a "grotesque" and "dangerous" surrender of British interests, with particular concern over a clause buried in the treaty's small print.

The deal requires the UK to notify Mauritius about military operations from the base on Diego Garcia.

The treaty says the UK will have to inform Mauritius of planned military attacks from the Chagos Islands

The treaty specifically states that "the United Kingdom agrees to expeditiously inform Mauritius of any armed attack on a third State directly emanating from the Base on Diego Garcia".

This requirement has raised significant security concerns because Mauritius is known to be an ally of China, prompting fears that sensitive military information could be passed to Beijing or other states hostile to Britain.

In recent months, Mauritius has also been strengthening its ties with Iran, further amplifying these concerns.

The treaty does not specify the level of detail that must be provided or whether notification must occur before military operations, leaving these aspects open to interpretation.

Former Defence Secretary Sir Grant Shapps told the Daily Mail: "Now we learn that we're not only paying Mauritius for continued access to our own territory, we've actually potentially signed away the right to act there without their say-so.

"In effect, we're bankrolling our own strategic retreat. It's a grotesque surrender of both sovereignty and responsibility."

Sir Gavin Williamson MP warned: "They've effectively given China, through the back door, a pretty amazing and unique position to have insight into what we're wanting to do, our objectives and motivations, which is very dangerous.

"The assumption will have to be that every time you do inform the Mauritians, China will also know."

Former Defence Secretary Sir Grant Shapps called the deal a 'grotesque surrender'

The Government has maintained that the treaty does not necessarily require details to be given in advance of military operations.

However, critics point out that this clarification is not written into the legal text of the treaty.

Former head of the Army Lord Dannatt described the arrangement as "the most bizarre defence arrangement I have ever come across".

Tory leader Kemi Badenoch criticised the financial aspects of the deal, claiming Donald Trump will be "laughing" because he's secured a "great deal at the expense of the UK".

The Conservative Party has labelled the agreement a "surrender tax" that, assuming two per cent inflation, actually amounts to £30billion.