12th April 1982 - US Woos Britain, Argentina Rejects Peace

12th April 1982 the Maritime Exclusion Zone around the Falkland Islands comes into effect. All Argentine air and sea movement within the 200 mile zone surrounding the islands is now subject to being fired upon by whatever British forces may be in the area

Meanwhile, the US Secretary of State's diplomatic peace mission is in London again. During dinner with the Prime Minister and Ministers, Haig is summoned away for a telephone call with Argentine Foreign Minister Costa Mendez. Costa Mendez confirms that despite some original softening in the Argentine line towards accepting the Haig plan (Plan involves cessation of hostilities, withdrawal of Argentine forces and a structured handover of sovereignty over time to Argentina with joint Argentine, UK and US Custodianship until handover is completed) Their line has now hardened and they refuse to accept the plan unless the UK accepts full priori Argentine sovereignty immediately

The Argentine position leaves no room for negotiation and war moves one step closer to inevitability

Diary Entry 12.04.82 Jim Rentschler, NSC Official for European Affairs, Alexander Haig Mission:
http://www.margaretthatcher.org/document/114324