PARIS (AP) -- President Nicolas Sarkozy threatened Sunday to pull France out of the European Union's coveted visa-free Schengen zone unless the bloc makes progress on protecting EU borders from illegal immigration.
Sarkozy's pledge on the hot-button theme of immigration came in a wide-ranging speech to thousands of supporters at a boisterous campaign rally, as polls show he faces a tough battle for re-election in April and May.
Unchecked immigration would thwart Europe's ability to take in and integrate new entrants, putting strains on social safety nets for the most disadvantaged across the continent, Sarkozy said to chants of "We're going to win!" against a sea of blue, white and red French flags.
"It's urgent because we cannot accept being subjected to the shortcomings of Europe's external borders," Sarkozy said, calling reform the "only way to avoid the implosion of Europe."
"But if I note within the next 12 months that no serious progress has been made in this direction, then France will suspend its participation in the Schengen accords until these negotiations are completed," he said.
The conservative president also pitched an effort to support purchases of European products within the continent, noting American government laws to support small businesses and domestic industries
"Why is it that Europe should forbid itself from what the United States, the world's most free-market country, allows itself?" Sarkozy said. "France will ask Europe adopt a 'Buy European Act' on a model of the 'Buy American Act.' That way companies that produce in Europe will benefit from European state money."
Sarkozy trumpeted his role in crafting a bailout fund called the European Stability Mechanism, for debt-laden EU countries like Greece that jolted financial markets and raised doubts about the euro.
He accused Socialist frontrunner Francois Hollande of playing politics with his call for a re-negotiation of that plan. Hollande says it relies too much on austerity and doesn't do enough to revive growth.
Hollande's campaign chief, Pierre Moscovici, fired back.
"Conservative leaders, who have been so quick to unite to defend the president, will appreciate his threat to pull unilaterally out of the Schengen zone at the same time that he calls for the signature of the austerity treaty in the name of European cohesion," Moscovici said, an apparent reference to endorsements that Sarkozy has received from German Chancellor Angela Merkel and other European conservatives.
Sarkozy also said EU nations that don't monitor their borders properly should be penalized, along the lines of sanctions that eurozone members can face if their state financing doesn't meet bloc-wide targets.
Much of the political debate in France in recent weeks has centered on the issue of illegal immigration and the country's ability to take in newcomers — typically a bete-noire issue of the far-right National Front party.
Critics have accused Sarkozy and allies in his conservative UMP party of taking a hard line against illegal immigrants in an effort to siphon off support from the extreme right before the first round vote on April 22.
Most recent polls show that Sarkozy would lose by a double-digit percentage margin to Hollande if, as expected, they are the two candidates to qualify for the decisive runoff on May 6.
The "Schengen zone" has been a banner EU achievement by making it easier for citizens to travel between its member countries. Some complain that it has also made it easier for illegal immigrants too to cross borders.
"Just as the far right is progressing in many European countries, Nicolas Sarkozy wants to open a harmful debate, where each country blames the others, and everybody faults immigration," Moscovici said in an e-mailed statement responding to the president's speech.
During the Arab world uprisings last year, Italy infuriated France and some other European countries by granting temporary residence permits to thousands of Tunisians who fled the violence at home. Many sought to join up with relatives and friends in France — Tunisia's former colonial overseer.
The Schengen zone applies to all 27 EU member states except Britain and Ireland. On Wednesday, bloc members Austria, Belgium, Britain, France, Germany, The Netherlands and Sweden called for an action plan to stem the tide of illegal migration into the union. The EU's executive commission is due to submit in May a report on the functioning of the Schengen system.
The made-for-TV rally, reminiscent of the start of Sarkozy's presidential run in 2007, was rich in visuals: He entered and exited the cavernous convention center in Villepinte, north of Paris, by glad-handing his gleeful fans. He frenetically shook so many hands on the way out that one of his cufflinks popped off, and he fumbled to tuck in his flailing shirt sleeve.
Sylvie Corbet contributed to this report.