Paris: President Francois Hollande was under mounting pressure to call his squabbling ministers to order on Monday as a row over the treatment of France’s Roma population rumbled on.

Against a background of opposition claims the Socialist-Green coalition is in disarray over the issue, Hollande has so far declined to get embroiled in the dispute triggered by Interior Minister Manuel Valls’s claim that most Roma in France will never integrate and should be sent back to their countries of origin.

Valls, who has also championed a controversial policy of dismantling illegal Roma encampments and deporting their residents, has been publicly criticised by at least three cabinet colleagues and the row has strained relations between Hollande’s Socialist Party and their junior governing partners, the Greens.

The opposition has been quick to pounce on an episode they say has once again exposed Hollande’s tendency to dither when confronted with difficult decisions.

“A government where you have some ministers organising attacks on other ministers cannot last,” said Francois Bayrou, the leader of the centrist Modem party. “Coherence has to be re-established and that is the responsibility of the president and the prime minister.”

The sniping at Valls from the Green and left of his own party continued unabated on Monday with Green Senator Esther Benbassa branding his attitudes on the Roma as “quite simply unacceptable.”

She added: “These (Valls’s) comments recall the darkest hours of our history. There is no such thing as a people who cannot be assimilated, only countries who do not make them welcome.”

Housing minister Cecile Duflot, the most senior Green in the government, has accused Valls of betraying France’s core values and urged Hollande to call the outspoken interior minister to order. Valls has denounced that claim as “unacceptable.”

Delphine Batho, a Socialist former minister who was sacked by Hollande in July for criticising government spending cuts, accused the president of double standards.

“I was pushed out the door supposedly as a show of authority, but there hasn’t been much of that on show in other cases,” Batho said.

Valls meanwhile was basking in the glow of evidence that his stance on the Roma issue has bolstered his status as the most popular minister in Hollande’s government.

A poll published at the weekend revealed that more than three in four (77 per cent) voters believe he was right to say Roma migrants should be “delivered back to the border.”

The minister was in unrepentant mood during a round of interviews on Sunday, in which he highlighted figures indicating that a disproportionate amount of petty crime in Paris is committed by minors who are nationals of Romania, from where the majority of recent Roma arrivals in France originate.

The extent to which the issue has gripped the country was reflected in the high-profile coverage given to a court case opening on Monday in which 27 members of three Roma families are accused of grooming children to become thieves.

Several of the accused are charged with people trafficking on the basis of evidence that some minors were traded between families in return for payment.

The defence contests the charges and says the payments could be explained by traditional dowry arrangements.

“I hope there will not be a judicial stigmatisation as there is currently a political stigmatisation,” said Alain Behr, a lawyer for one of the defendants.

Earlier this month, a magistrate in the southern city of Toulouse sparked outrage during his summing up of a case in which he told four defendants: “Don’t you think France has had enough of Roma stealing?”