Type 42 destroyer HMS York was last night in waters off the islands' capital Port Stanley - spearheading a new British task force in the escalating oilfield drilling row with Argentina.
The survey vessel HMS Scott has also headed to the windswept isles and is alongside the warship.
The giant oil supply tanker RFA Wave Ruler will be there soon.
And the three new arrivals, previously sailing elsewhere in the vast Atlantic, will make up a four-strong seaborne force with the Falklands' permanent patrol vessel HMS Clyde.
A senior Navy source said HMS York had been sent as a "deterrent" to Argentina as tensions between London and Buenos Aires rise over the drilling operation by four British-based oil firms, due to begin next week.
The source added: "She will discourage the Argentines from trying anything with our shipping.
"If they do, the Navy are there to stop them."
The Naval mission will evoke memories of Rod Stewart's song Sailing, which became associated with the Falklands War after being used as the theme tune to a BBC documentary about the aircraft carrier HMS Ark Royal.
Argentina, which still claims the Falklands and its surrounding seas despite its crushing defeat in the war, is furious at the Brits' plan to drill at least seven wells off the islands.
On Tuesday it tried to implement a blockade by issuing a decree banning any merchant ships from reaching the UK territories without its permission.
And last week it detained a cargo ship in a port near Buenos Aires, claiming it was ferrying steel oil pipes to the islands.
But as the row grows, The Sun can reveal the Naval presence is not the only deterrent mounted by Britain.
There are now more than 1,000 Armed Forces personnel in the region, plus four Eurofighter Typhoons, a Hercules transport plane, a Vickers VC10 refuelling aircraft and two Sea King helicopters.
Referring to the Navy's manoeuvring, the source said: "It has been done very quietly so as not to look too provocative.
"But the Argentines are in no doubt that we are there now."
Admirals are determined not to make the same mistake they did in 1982, when their plan to withdraw the Falklands' regular patrol boat encouraged General Galtieri's junta to invade. (lol, thatcher cut it, the navy didn't choose to withdraw it)
Experts claim there could be 60BILLION barrels of black gold under the islands' coastal waters.
The Ocean Guardian drilling rig will arrive tomorrow after an 8,000-mile journey from Scotland.
And next week Desire Petroleum will become the first company to begin explorations at a potential field known as Liz.
They deny it is named after the Queen, but rather the wife of a company director.(realy sun? realy? i dont think anyone thought it was named after the queen...)
Tory MP Andrew Rosindell last night called on the Government to tell Argentina's ambassador in Britain that the blockade bid is "unacceptable".
A Navy spokesman said: "The Government is fully committed to the South Atlantic Overseas Territories."
although there are alot of storys about the build up of tensions, this is the only one i can find about a uk forces build up, tho it got air time on the today program
edit: beter sauce with a broader focus http://news.bbc.co.uk/1/hi/world/americas/8521429.stm ta brewsternorth