This statement came after the 700,000-strong demo last Saturday in Milan called by the CGIL, the biggest of the three confederations.
Several school students' organisations are also calling for a series of school occupations on the day the war starts.
On Tuesday 11 Italian dockworkers went on strike for the last hour of their shift to protest against the United States using their workplaces to ship military hardware to the Gulf.
"We're striking against the Italian ports being involved in the preparation for a military operation in Iraq," the three biggest dockworkers' unions said in a joint statement on Monday.
The Italian government has had to employ the Army to move the US military equipment from Camp Darby, its key installation near the western port of Livorno (Leghorn).
Italian Prime Minister Silvio Berlusconi has been one of Washington's closest allies in the Iraq crisis, but polls show 70 percent of Italians oppose war, even if sanctioned by the United Nations.
The right wing government is deeply divided on this issue. The smaller coalition parties that originated in splits from the former Christian Democracy cannot ignore the Pope's antiwar message (for it reflects the mood of many of their voters). Today debate on the Iraq war in the Italian parliament will add another factor of potential crisis for a government which has already been weakened by the two 24 hour general strikes last year and the massive protest wave that has been shaking Italy in the last period.