"This means that 86 per cent of NSW is accepted nationally as disease free and movements across the border from this area of NSW will be eased from Friday, 1 February," said the state's Primary Industries Minister Ian Macdonald.
He described it as a significant step towards a return to normal for the horse industries in all states.
It has been 51 days since the most recent report of flu infection on any NSW property, and 33 days since the last positive laboratory test - for a case believed to have been three weeks old.
The national agreement means the lifting of quarantine requirements for horses moving out of the state from NSW's green zone.
The current green zone will be reclassified on February 1 as white under the state's protection plan.
"This will really benefit horse owners living along the border in southern NSW who have had to contend with stringent border crossing restrictions, even though the area has been disease free for some time.
Until this change, all horses moving into Victoria from the NSW green zone needed a permit and had to spend up to two weeks in quarantine in both states.
"Now, all that will be required is a Travelling Horse Statement (THS) in NSW and a permit from the DPI in the destination State."
The THS can be filled out online and downloaded from the NSW Department of Primary Industries website. This is the same document that NSW horse owners need to move horses within the green zone.
Requirements for horse movements within the new NSW white zone will be the same as for the current green zone. All other movements between EI zones in NSW remain unchanged.
Mr Macdonald said New South Wales remained on track to be flu-free by mid-March. When this happens, all that will be required to move a horse in NSW will be a Travelling Horse Statement (THS).
"This is good news for our horse industries, but it hinges on not one more case in the coming weeks.
"Good biosecurity, reporting of suspect horses and sensible movement of animals is more crucial to the campaign than ever. There is no room for complacency; one undiagnosed sick horse could bring down the house of cards."
More details: www.dpi.nsw.gov.au/agriculture/livestock/horse/influenza