Nicolas Sarkozy, the French President, made a calculated lurch towards protectionism and Euroscepticism yesterday in an attempt to rescue his presidency.

Before a crowd of 40,000 tricolour-waving supporters near Paris, he promised to suspend France's participation in the Schengen open-borders agreement unless migration was placed under the direct control of EU governments within 12 months. He also called for a "Buy European Act" to reserve part of all state purchases within the EU for European industry, especially small businesses. If Brussels failed to make progress towards mirroring the Buy American Act within 12 months, he said, France would go ahead unilaterally – breaking European trade law.

Six weeks before the first round of the presidential election, President Sarkozy is trailing the Socialist candidate, François Hollande, in the opinion polls. Yesterday's mass rally at Villepinte – gathering Sarkozy loyalists by bus and train from all over France at a cost of €4m – had been billed as his last chance to change the momentum of the campaign. The President gave a confident, energetic performance, in which the words "je" and "France" were repeated in almost every sentence. He addressed the mainly young crowd from a large white platform swept by red, white and blue lights.

Celebrities in the audience included the actor, Gérard Depardieu, and the president's wife, Carla Bruni-Sarkozy. She looked on serenely, despite suggesting in a widely-mocked interview on Friday that her husband worked so hard for the country that she feared that he might "drop dead".

The Sarkozy campaign had promised new ideas to revive a campaign which has been playing, unsuccessfully, with hard-right issues such as immigration and the alleged threat to the French way of life from halal meat. In the event, Mr Sarkozy came up with a double-theme carefully calculated to appeal to both the nationalist right and the nationalist left: Euro-bashing and protectionism. The President claimed that he had "saved the euro and the EU" in the past 12 months. He had always been a convinced European, he said, but the EU could no longer be an "abstract" idea, served by an "elite looking at itself in the mirror".

The Schengen agreement, which allows people to travel freely without border checks, "could no longer cope with the gravity" of the immigration threat, he said. He called for a government of the Schengen zone, which would bring together national governments to take emergency measures to control migrants.