Engineers in the UK have been found using software developed in Russia and Belarus for the operation of the country's nuclear submarines, breaching Ministry of Defence regulations, The Telegraph reports.

The software, intended to be created by specialists with secret clearance, was partly outsourced to developers in Siberia and Belarus, prompting the Ministry to launch an investigation in summer 2022, which concluded in February 2023.

The investigation revealed that Rolls-Royce Submarines, responsible for managing the UK's nuclear submarine fleet, had outsourced software development to WM Reply, a consulting firm.

WM Reply involved Belarusian developers, including one working from Siberia.

The company allegedly attempted to conceal the developers' locations and even considered using the names of deceased UK citizens.

Despite these actions, Rolls-Royce Submarines claimed no serious national security impact, as WM Reply employees did not access protected server information.

Following the investigation, Rolls-Royce Submarines ceased collaboration with WM Reply.

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In 2023, the UK and Australia advanced their collaboration under the AUKUS pact, a trilateral security agreement with the US.

The UK Ministry of Defence has awarded a £3.95 billion (A$7.5 billion) contract to BAE Systems to progress the development of the next-generation SSN-AUKUS nuclear-powered attack submarines.

This initiative will see the first British submarines delivered in the late 2030s and the first Australian submarines in the early 2040s​.

France was outraged by the pact, as Australia was set to purchase submarines from France, in accordance with a deal signed in February 2019.

Australia was to purchase 12 conventional submarines from France for US $50 billion, which the French called the "contract of the century."