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Eric Zemmour warned against an “emotional response” to the crisis and suggested France follow the UK policy, which is to accept refugees with family already there.
Mr Zemmour is a populist, anti-immigration candidate who has set himself up to outflank Marine Le Pen, the most well-known of the far-right candidates in the presidential election.
“If they have ties to France, if they have family in France … let's give them visas,” he said.
“It's a question of assimilation. There are people who are like us and people who are unlike us.
“Everybody now understands that Arab or Muslim immigrants are too unlike us and that it is harder and harder to integrate them. We are closer to Christian Europeans.”
Since the Ukraine war, Mr Zemmour has been criticised for previous comments in support of Russian President Vladimir Putin.
His support has fallen by 3 to 4 points to about 12 per cent in voter surveys since the Russian invasion of Ukraine.
On Tuesday, he was one of 12 candidates to have qualified to run in the election.
Incumbent Emmanuel Macron is at 30 per cent and Ms Le Pen is in second place with 18 per cent.
In September 2020, Mr Zemmour tweeted that he favoured a “Russian alliance” and that Moscow was “the most reliable ally, even more than the United States, Germany or Britain".
He has condemned Russia's invasion of Ukraine but has also said the West should take its share of the blame.
Ms Le Pen was also criticised last week after photos of her with Mr Putin from 2017 resurfaced.
“The Vladimir Putin of five years ago is not exactly that of today,” she responded, saying he had “crossed a red line” in attacking Ukraine.
Ms Le Pen said the war had “partly changed” her view.
“Yes, it’s an authoritarian regime, historically and in culture — even if we are judging by our western norms, which are not Russian norms,” she said.