However, he said if the right choices are made the Government can steer the country out of rough waters.
Brian Cowen said the global outlook is more uncertain than it has been for decades but he said the country cannot afford to indulge in a burst of borrowing to fund a big increase in current spending.
He urged councillors to put the country first even if that means making hard choices.
The Taoiseach accepted that the budget was not popular and that the Government did not get everything right.
He said the number one priority was to reduce the budget deficit.
The meeting of the party's National Councillors' Forum will also be addressed by Tánaiste Mary Coughlan, Education Minister Batt O'Keeffe, Agriculture Minister Brendan Smith, and Transport Minister Noel Dempsey.
All the Fianna Fáil members of cabinet have been invited to Tullamore and more than 200 councillors from all parts of the country are expected to attend the meeting.
The Irish Cattle and Sheep Farmers Association are demonstrating outside the meeting over the Budget cuts.
The education and agriculture cuts, the handling of the medical cards issue and the general way the party is communicating its message is worrying councillors, who have to face the voters in next year's local elections.
