Michael Fallon, the defence secretary, will announce plans to bolster the Falkland Islands garrison amid fears of a renewed threat from Argentina.
The south American nation is feared to be increasing military expenditure. Senior ministers in the country have also made a series of increasingly aggressive statements about the islands in recent years.
Michale Fallon said: "The threat remains. It is a very live threat. We have to respond to it."
He said reports that Russia is working on an agreement to lease 12 long-range bombers to Argentina which could be used to support a renewed attack are unconfirmed.
"We do need to modernise our defences to ensure that we have sufficient troops there and that the islands are properly defended in terms of air defence and maritime defence.
"The threat, of course, to the islands remains but so does our commitment to being absolutely clear that islanders have the right to remain British and the right to proper protection by our forces.
"It is our general view that the threat has not reduced. Argentina still, sadly, maintains its claim to the islands 30 or more years after the original invasion and the war and we have to respond to that."
A spokesman for the Ministry of Defence added: "There is a defence review and an announcement will be made about it. There will be a full statement by Michael Fallon."
Military analysts have previously argued that without an aircraft carrier, Harrier jump jets or the ability to deploy a task force, the islands could be seen as an easy target for Argentina.Read more HERE
(RG) I don't think this is any kind of saber rattling on the part of the British government, this is just good housekeeping and sending a message to the Argentinians that like in 1982 will will be prepared to use force to defend the Islands from aggression. We have as much right to send extra troops to the Falklands as we do to send extra troops to Blackpool. The Argentinians can buy or borrow as many jets from China or Russia or anywhere else, but think about it our Forces are battle hardened from fighting in Iraq and Afghanistan and even if they could invade again which they cannot they would be defeated yet again.