French Finance Minister Michel Sapin was heavily criticised on Wednesday after he accused Belgian authorities of
"naivety" over the spread of Islamist extremism.
"I think there was a will, or a lack of will, on the part of some (Belgian) authorities... perhaps also a kind of naivety," Sapin said Tuesday, suggesting that they "thought that to encourage good integration, communities should be
left to develop on their own."
Speaking to French TV station LCI, he added: "But we know, and France perhaps knows better than others, that this is not the right answer. When a neighbourhood is in danger of becoming sectarian, we should (implement) a policy of integration."
Sapin's words, coming a day after the suicide bombings in Brussels, were slammed in France and Belgium.
"It is indecent when people are suffering, are in shock. We need solidarity, not lectures," said Belgian Socialist politician Laurette Onkelinx.
A member of Sapin's own French Socialist party, Francois Lamy, described the finance minister's statement as "just shameful".
The row had echos of the days after the Paris attacks when French media and certain politicians pointed the finger at Brussels for failing to nullify the Islamist extremist threat that had grown right under its eyes.
The fact many of the attackers who killed 130 people in Paris were from Brussels and that the coordinated attacks were clearly planned in hideouts throughout the country, left many in France with the view the Belgian authorities and intelligence services were guilty of huge failings.
“The wretched attacks were prepared abroad and mobilised by a team of actors living on Belgian territory,” said interior minister Bernard Cazeneuve at the time, after summoning his Belgian counterpart for talks.
And following the arrest of Salah Abdeslam, the chief surviving suspects from the Paris attackers, some in France wondered why it took Belgium a full four months to find him, when he was seemingly right under their noses.
"Either Salah Abdeslam is very clever or the Belgian services are stupid, which is more likely," French MP Alain Marsaud commented after the capture.
The two countries also clashed in February when Brussels decided to step up checks on the French border to prevent migrants, displaced from the Jungle camp in Calais, from setting up a similar sprawling encampment outside ports in Belgium.
France called the move "odd" and "not based on reality".
However the leaders of the two countries have tried to present a united front, particularly since Brussels has joined Paris in the growing list of European cities scarred by a major terrorist attack.
French Prime Minister Manuel Valls sought to distance himself from his colleague's words, saying he did not want "to lecture our Belgian friends".
"We closed our eyes, everywhere in Europe and including France, to the rise of extremist Salafist ideas in neighbourhoods where a mix of drug trafficking and radical Islam have led astray ... some of the youth," Valls told Europe 1
An aide to Sapin told AFP he had not wanted to single out Belgium and was talking more generally about the terrorist threat.
The aide said Sapin had sent a message to his Belgian counterpart, Johan Van Overtveldt, apologising for the "controversy".