All intercounty GAA fixtures have been called off for this weekend. The decision was taken yesterday after consultation between Croke Park officials and the Department of Agriculture. As they face the prospect of an unprecedented crisis, with the threat of a foot-and-mouth epidemic hanging over the country, the GAA authorities have said they will review the situation next week.

Whereas all concerned were anxious not to panic or pre-judge the situation, GAA sources accepted that any worsening of the problem could wipe out the spring programme of fixtures. Casualties of the coming weekend include a full series of National Hurling League fixtures, the AllIreland club semi-final replay between Sixmilebridge and Graigue-Ballycallan and the Sigerson Cup finals weekend.

Although foot-and-mouth disease caused widespread disruption during the previous outbreak in Ireland 60 years ago, wartime travel restrictions already in place helped to contain the disease. The AllIreland championships took place, but with Tipperary and Kilkenny excluded.

From a GAA perspective, any longterm impact on the championship would be disastrous considering the revenue implications for the development of Croke Park and television coverage.

The club championships are now in serious doubt. With Dublin's St Patrick's Day parade set to be called off to prevent movement of people to the capital, it's hard to see how the All-Ireland club finals can proceed on their traditional date - even if the hurling semi-final replay gets sorted out.

Yesterday began with the announcement that the London-Louth hurling league match had been "postponed indefinitely" and the private acknowledgment that London's league season was in doubt. The news of the investigation in South Armagh escalated the situation, and by yesterday afternoon, the announcement of a full postponement was made.

"We toyed with the idea of calling off any games involving northern teams," said GAA spokesperson Danny Lynch, "but after discussing the matter with the Department of Agriculture, we felt it would be better to prevent any movement of people to our matches. It's heartbreaking to have to call off the Sigerson Cup, but we had absolutely no doubt that it was the right thing to do."

Padraig Duffy, the chairman of the Games Administration Committee (GAC), will have to sort out the fixtures' chaos if and when the all-clear is given.

"Everything at a national level was called off, anything involving the crossing of county boundaries by players, officials and spectators. That meant the full programme. We'll see by next Monday or Tuesday what the situation is and review our position then.

"It's hard on all involved, but the national interest transcends the GAA and we had no choice. We don't know what the future holds even if any outbreak is contained. The whole issue could come down to whether the National Leagues can be finished in time. A couple of postponements can be sorted out, but we just don't know at present."

The interval before an area which has been in quarantine can be given the allclear can be anything between one and two months, which doesn't leave much time for the smooth running of the championship - due to begin in two months.

This year the GAA football championship was due to introduce an All-Ireland qualifying competition for teams beaten in the first round. The qualifier is due to add 29 further matches to the schedule, but this departure must be open to reconsideration if the championship is delayed.

The higher education Sigerson and Fitzgibbon Cups are also seriously affected. Tomorrow the Sigerson football tournament was to start in Sligo, with the local IT as hosts. It was due to run from quarter-finals to the final on Sunday in Markievicz Park.

Its postponement creates a major fixtures' headache. "It's upsetting," said Des Cullinane, chairman of the controlling Comhairle Ard Oideachais, "but we had no choice in the matter. We'll have to sit down with the GAC and see if we can get another date, but with the under-21 championship about to start and county championships getting under way in April, we don't have a lot of options."

Next week the hurling equivalent, the Fitzgibbon Cup, was due to be played in UCD's Belfield campus. Dave Billings, the UCD Games Development Officer, acknowledges that the prospects of the Fitzgibbon being played are bleak. "I'm very sorry for all the people in Sligo IT who worked so hard to put on the Sigerson, and I know we may well see the Fitzgibbon go the same way. But this is a national emergency and all sports have to recognise that."

If the Sigerson quarter-finals are played separately, there is a chance that the semifinals and final may also be played on a midweek basis, and similarly the Fitzgibbon. Alternatively, the competitions could be put back to the autumn, but according to Billings, "the academic year would make a nonsense of that".

Other GAA events affected include Leinster Council fixtures in the O'Byrne Cup, provincial minor football league and provincial junior hurling tournament. AIB's reception for winners of its provincial club players awards has also been called off.

The annual congress of Cumann Peile Gael na mBan, the women's football association, due to be held in Cavan at the weekend has been called off "in the national interest" according to PRO Finbarr O'Driscoll.

Also, all camogie matches, including the All-Ireland Colleges semi-finals, scheduled for this weekend have been cancelled.

On a related Fitzgibbon Cup matter, the University of Limerick - expelled last week from the competition for fielding an unregistered player - have not yet lodged an appeal with the GAC. Failure by UL to lodge it by this evening would mean that UCD advance to the tournament weekend, which they are to host - assuming it takes place.