PARIS -- France’s lower house approved by a large majority on Sunday a bill that would tighten asylum rules after tense debates that created the first cracks within President Emmanuel Macron’s party.

One member of Macron’s party, Jean-Michel Clement, voted against the bill and said he would leave the majority.

“I am not sure we’re sending to world citizens the universal message that has always been ours,” the lawmaker said in a statement following the vote late on Sunday.

The French National Assembly voted in favour of the legislation by 228-139, with 24 abstaining. Debates are due to follow in the upper house, the Senate, in June. The National Assembly will have the last word on the bill.

A dozen lawmakers in the more than 300-seat majority have voiced concerns over the bill in recent days, not enough to defeat the government but the most serious sign of unease to date for Macron’s two-year-old political movement.

Embarrassingly for the government, far-right leader Marine Le Pen and her fellow National Front lawmakers voted in favour of some of the bill’s articles. 

Before the vote, Macron’s party whip, Richard Ferrand, had warned his members that although abstaining would only be considered a “venial sin” by party hierarchy, voting against the bill would constitute a “mortal sin.”

The legislation was criticized by human rights groups and leftist parties and represented a key test for the unity of Macron’s centrist party.

It doubles to 90 days the time in which illegal migrants can be detained, shortens deadlines to apply for asylum and makes the illegal crossing of borders an offence punishable by one year in jail and fines.

The government has said it wanted to be both firm and fair on immigration, which has been a major political issue since hundreds of thousands of migrants fleeing war and poverty in the Middle East and Africa started moving to Europe.

The bill would also make it easier for minors to get asylum and aims to halve the time it takes for authorities to process any asylum request.