The North's Minister of Agriculture, Mrs Brid Rodgers, said last night that there would be no relaxation in guidelines on foot-and-mouth and that some controls were to be tightened.
The Minister had been expected to relax guidelines issued last week, including a recommendation that all sporting fixtures be postponed. But following the outbreak in Co Louth, restrictions are to be tightened.
"The current range of controls will remain in place. In fact we have to add controls to achieve greater protection," she said.
Department of Agriculture personnel have joined RUC officers at Border crossings within 10km of the Jenkinstown outbreak.
The Minister praised the North's farming community and the wider public for their co-operation to date. But she warned that further vigilance was necessary.
She said there was an urgent need to find the source of the Louth outbreak, but it was unlikely to be Meigh. "The time lag strongly suggests that there may be other intermediate sources of infection which we have yet to discover."
Restrictions on animal movements in south Armagh had been eased just hours before confirmation of the foot-and-mouth outbreak at Jenkinstown.
The Ulster Farmers Union said it would support a cull of animals in the Border area in an attempt to contain the virus. Its spokesman, Mr Joe McDonald, said a pre-emptive cull might help to prevent the disease from spreading.
He called for a cross-border approach.
The Sinn Fein president, Mr Gerry Adams, called on anyone who knew the whereabouts of up to 60 sheep still unaccounted for to contact the authorities.
The Ulster Unionist Council has postponed its annual general meeting, scheduled for tomorrow in Belfast.