Despite hold on Diego Garcia, UK’s move to return Chago Islands sparks security concerns

BELFAST — Backed by the White House, the United Kingdom agreed to hand sovereignty of the Chagos Islands to Mauritius today, after 13 rounds of negotiations over the former African colony, but will continue to retain control of the UK-US Diego Garcia military base for an initial period of 99 years.

London hailed what it called a “historic agreement” and focused on the new legal status of the military base, saying that for “the first time in more than 50 years, the status of the base will be undisputed and legally secure.” But the decision drew swift criticism from opposition lawmakers and analysts who questioned its strategic value in light of China’s close ties with Mauritius.

The agreement is “subject to the finalisation of a treaty and supporting legal instruments,” stated a supporting UK and Mauritius joint statement.

The UK cut off the Chagos Archipelago, covering around 55 islands that sit in the middle of the Indian Ocean about 1,700 miles south of the tip of India, from Mauritius over 50 years ago, expelling its population and renaming the region the British Indian Ocean Territory (BIOT). It then granted the US permission, on a 50 year basis, to use BIOT, including Diego Garcia for defense purposes — an agreement that renewed in 2016 for an additional 20 years.

The UK said that “without” the new agreement signed today, “the long-term, secure operation of the [Diego Garcia] military base would be under threat, with contested sovereignty and legal challenges — including through various international courts and tribunals.”

It added, “The agreement demonstrates the UK government’s commitment to safeguarding global security and averting threats to peace and prosperity in the Indian Ocean and wider Indo-Pacific. It sees Mauritius assume sovereignty over BIOT, with the UK authorised to exercise the sovereign rights of Mauritius on Diego Garcia.”

The new agreement also commits London to a “package of financial support” to Mauritius, based around an undisclosed annual payment, over the length of the pact.  “More broadly, the UK and Mauritius will cooperate on environmental protection, maritime security, combating illegal fishing, irregular migration and drug and people trafficking within the Chagos Archipelago,” according to the joint statement.

In a separate statement, US President Joe Biden, welcomed the pact and stressed that the remote Indian Ocean base “plays a vital role in national, regional, and global security,” and “enables the United States to support operations that demonstrate our shared commitment to regional stability, provide rapid response to crises, and counter some of the most challenging security threats we face.”

The base is critical for US air and naval operations across the Indo-Pacific in particular in support of B1-B Lancer long-range bomber deployments.

Additionally, the site’s Naval Support Facility offers “logistical support for forces operating in and around the Persian Gulf and Indian Ocean, and hosts a maritime pre-positioning squadron as well as detachments from the U.S. Fleet and Industrial Supply Center, Air Mobility Command, Pacific Air Force, and the 21st and 22nd Space Operations Squadrons,” according to the Congressional Research Service [PDF].

On the British side, some 40 personnel from the Royal Navy and Royal Marines are said to be stationed at the base.

In the UK, a number of analysts and opposition lawmakers from the Conservative Party criticized London’s decision — even if the Conservatives originally opened negotiations with Mauritius in 2022, which led to today’s agreement. (A year before that the United Nations court ruled the UK had no sovereignty over the islands and said they should be handed back to Mauritius.)

On X, Grant Shapps, a former British defense secretary, labelled the move “absolutely appalling” and a “deeply regrettable act.”

Similarly, Tom Tugendhat, a Conservative party leadership candidate, called it “a shameful retreat undermining our security and [one] leaving our allies exposed.” He argued the Foreign, Commonwealth and Development Office had “negotiated against Britain’s interest.”

His rival for the leadership position, Robert Jenrick, equally condemned the agreement. “This is a dangerous capitulation that will hand our territory to an ally of Beijing,” he claimed on social media.

“You can bet a whole pot of aid money that those other islands,” besides Diego Garcia, “will be of great interest to PRC [People’s Republic of China] intelligence/special ops…” said David Blagden, associate professor at the strategy and security institute, University of Exeter. The potential for Beijing, which has a free trade agreement with Mauritius, to make a play for influence on the islands has been hotly debated before.

UK naval analyst Emma Salisbury wrote on X, “I have a nasty feeling that this UK deal with Mauritius over the Chagos Islands will be seen by historians as a considerable strategic mistake — particularly given the importance of Diego Garcia to UK/US security.”

In 2022, the Mauritius ambassador to China penned an op ed for a Chinese state broadcaster highlighting the countries’ “special relationship” and their “cooperation [in] all spheres, from economy, trade, culture, tourism, health and sports among others.” The Spectator, a conservative-leaning UK political publication, reported today that banks from China and Mauritius signed a “bilateral currency agreement less than a month ago.”