PARIS (Reuters) - Nicolas Sarkozy, seeking to return to power as French president, said on Tuesday he would tax U.S. imports if Washington turned its back on international trade and climate accords under Donald Trump.

Five days from a primary contest where polls predict Alain Juppe will win their party ticket for the presidential contest, Sarkozy is seeking to tap voter fears of globalisation and portray himself as a harder hitter than his chief rival.

In an RTL radio interview, Sarkozy, 61, president from 2007 to 2012, said: "There's no reason why Europe should not protect and defend its interests.

"Protectionism is not the danger to peace in the world. The big danger to world peace is if China, Brazil, Russia and the United States protect and defend their interests with all their might while Europe fails to protect its interests."

If he were elected president next May he would convene a meeting of European Union leaders to decide to reserve public works contracts for firms who do the work in Europe, Sarkozy said.

The European Commission, the EU executive, does the negotiating on trade issues, meaning France would have to convince fellow countries rather than dictating the EU's stand.

If Trump reneged as he has said he would on the international Paris climate change accord, Sarkozy said he would ensure France and Europe imposed a carbon tax of 1 to 3 percent on all U.S. goods coming into the continent. [nL8N1DE0SN]

Sarkozy also said he would cut tax, unlike Juppe, who wants to raise value-added sales tax by one percentage point.

Juppe, who has nurtured the image of a consensual statesman who can beat off a challenge from the anti-immigrant National Front party, says France must protect its trade interests but he stops well short of the stand proposed by Sarkozy.

Juppe told reporters earlier this week Europe should veto attribution of favored trade status to China because Beijing was "not really playing" the game.

"But protectionism is a word of the past," he said. "It's a stand that sends us down the road of the National Front, of a France that turns inwards."

Opinion polls show Juppe will beat National Front leader Marine Le Pen if the two face off in the second round of the presidential election.

His Les Republicains party's two-round primary contest is on Nov. 20 and 27.

Socialist President Francois Hollande has yet to say if he will run but polls predict he will not win January's Socialist primary.

(Writing By Brian Love; Editing by Janet Lawrence)