The UK Royal Navy will require an additional 4,000 crew members to operate two new aircraft carriers and the nuclear submarine fleet, the UK National Defence Association has said.
According to the group of former military leaders, the country faces a serious manpower shortage and may be forced to recruit crew members from foreign countries.
Retired vice-admiral Sir Jeremy Blackham said: "From a naval point of view there is a serious problem.
"It's said to be, when I last spoke to the fleet commander, of the order of 3,500 to 4,000 people."
The association claimed this trend will also affect the Royal Air Force (RAF).
Since the 2010 defence review, the Royal Navy has lost 5,500 personnel, while the RAF lost 8,500, The Independent reported.
Blackham said:"There is a serious manpower problem, which will negate some of the investment we are making in equipment unless it is addressed.
"There is a deal on the table but it falls very, very far short. The navy has been looking at the possibility of recruiting from other appropriate nations to assist with manning ships."
The navy is planning to recruit up to 1,000 personnel from countries, including the US, Canada and Australia to fill gaps in critical specialist engineering jobs in the next decade, The Telegraph reported.
The Royal Navy's first Queen Elizabeth-class (QE) aircraft carrier, HMS Queen Elizabeth, is expected to be commissioned in May 2017, followed by its sister ship, HMS Prince of Wales, a few years later.
UK has currently committed to spend 2% of its national income on the defence sector, raising the Ministry of Defence's (MoD) budget by 0.5% every year until 2020.
The government said the additional financial funding will support the UK MoD to invest on new projects, such as replacing the Nimrod maritime patrol aircraft.
Image: The Royal Navy's HMS Queen Elizabeth is expected to be commissioned in May 2017. Photo: courtesy of UK Royal Navy.