Argentine President Cristina Kirchner signed the decree, ratcheting up tensions between Argentina and Britain over Las Malvinas, the Spanish name for the islands they warred over in 1982 at the cost of almost 1,000 lives.
"All ships that wish to move between ports in continental Argentina and ports in the Malvinas islands, or that wish to cross Argentine territorial waters as they head to the islands" require prior permission, it said.
Kirchner's chief of staff Anibal Fernandez left no doubt the move was intended to clamp down on shipping that might be helping Britain as it launches operations to explore the region's oil and mineral reserves.
The decree seeks to achieve "not only a defence of Argentine sovereignty but also of all the resources" in the area, Fernandez explained, adding that a high-level permanent committee would be set up to monitor the shipping.
Anger in Argentina over the Falklands, which has bubbled below the surface for much of the last three decades, has threatened to boil over in recent months as Britain prepares to launch drilling operations.
Argentina has lodged a protest with London about drilling in the seabed around the windswept islands, which contains up to 60 billion barrels of oil, according to geological studies quoted in the British media.
A tug boat hauling a British exploration rig will arrive any day to start oil prospecting and the issue already came to a head earlier this month when Buenos Aires blocked a shipment of pipes it said was bound for the Falklands.
Argentine authorities boarded the foreign flagged "Thor Leader" in the southern port of Campana after learning it was about to take on a cargo of pipes used in the oil industry and apparently destined for the Falklands.
Buenos Aires is furious that London continues to skirt UN resolutions calling on both governments to renew a dialogue on the sovereignty of the Falklands.
"We wish to reaffirm the obligation to resolve the differences between Britain and us in the framework of international law and United Nations resolutions," Kirchner said on Tuesday.
Britain in January rejected Argentina's latest claim to the islands, which it has held and occupied since 1833.
The Foreign Office in London sought to play down Argentina's latest move in the row by issuing a bland statement, pointing out the obvious about the legal position.
"Regulations governing Argentine territorial waters are a matter for the Argentine authorities. This does not affect Falkland Islands territorial waters which are controlled by the island authorities," a statement said.
It said Argentina and Britain were "important partners" and pledged to "cooperate" on issues in the South Atlantic, where the Falklands are located.
Buenos Aires has urged a solution along the lines of what Britain agreed for the Chinese territory of Hong Kong.
Britain and Argentina's rival claims of ownership over the Falklands exploded into war in 1982 after Argentine military rulers seized the islands, only to be defeated and expelled by a British naval force.
The conflict lasted 74 days and cost the lives of 649 Argentine soldiers and 255 from Britain.