PARIS (Reuters) - A French lawmaker who broke with President Emmanuel Macron’s party over a parliamentary vote on immigration said it should open up to more debate, voicing concern that the legislature could become weakened.

Jean-Michel Clement on Sunday became the first lawmaker to leave Macron’s two-year-old Republic on the Move (LREM) party, after joining up along with enthusiasts from across the political spectrum ahead of parliamentary elections last year.

The defection is the first tangible sign of unease within the LREM about both a perceived lurch to the right since Macron’s election and an insistence on speedy debates that critics say undermines the principles of parliamentary democracy.

Clement -- who took a stand against a bill to tighten asylum rules, while 14 others from LREM abstained -- said in an interview with Reuters there was a lack of debate within the disparate collective, which needs to show it has staying power.

“The time for debate within LREM is two hours a week all together,” said Clement who was a member of the Socialist Party before joining Macron. He will now sit in parliament as an independent.

“It’s a group that’s enriched by its diversity, and as soon as there’s a differing voice, should it be considered a discordant one?”

Macron clinched the presidency a year ago weeks before his upstart party, which defines itself as neither left or right, won a comfortable majority in parliament, sweeping away long-standing political forces.

The 40-year-old president has so far passed bills with ease, and Sunday’s vote was no exception, with the French National Assembly passing the legislation by 228-139 before the bill heads to the upper house, or Senate, for more debates.

But a dozen lawmakers from Macron’s party had voiced unease in the run-up to the vote over a bill that doubles to 90 days the time in which illegal migrants can be detained and shortens deadlines to apply to asylum, among other measures.

And in a potential sign of broader malaise, some 99 LREM lawmakers had not turned up for the vote, which one lawmaker who did vote said was not just due to the debate taking place on a Sunday evening during school holidays.

“For many, this bill does not fit in with their political sensitivity,” said that lawmaker, who asked not to be named.

Many Socialists had joined Macron’s ranks in the belief he would implement a more welcoming attitude towards refugees. During his presidential campaign, he praised German Chancellor Angela Merkel for “saving Europe’s dignity” on refugees.

Human rights groups and leftist parties have criticized the plans as heavy-handed and an erosion of the rights of refugees, while the government has said it wants to be firm but fair on immigration, and help those with strong cases for asylum, including by speeding up approval processes.

“When you have a bill that clumsily mixes together these two issues (immigration and asylum), of course you’re going to get contradictions,” said Clement, a 63-year-old former lawyer.

The first public signs of disquiet within LREM ranks come as Macron grapples with the biggest test yet of his reform appetite from outside political circles as unions press on with train strikes in protest at an overhaul of the state-run rail operator.

Asked whether the lack of party dialogue was down to Macron’s style of governing, Clement said “not everything” could necessarily be blamed on the president.

But he added there was a risk that institutions in France were drifting towards a situation where “parliamentary control is non-existent”.

Macron’s government has already chosen to pass reforms by decree on some occasions, including a liberalization of labor laws, bypassing parliament.