French far-right leader Marine Le Pen accused two banks on Wednesday of launching a "banking fatwa" to silence her National Front party by closing bank accounts of hers and her party's.
The banks said they had acted within regulatory requirements but declined to offer fuller explanations.
Le Pen is smarting from defeat in this year's presidential and parliamentary elections, during which she accused French banks of being politically biased for not lending to her campaigns.
"This is an attempt to suffocate an opposition party, and no democrat should accept that," Le Pen told a news conference, calling on President Emmanuel Macron and other political parties to back her National Front (FN).
Le Pen said the FN would file a complaint against Societe Generale and its subsidiary, Credit du Nord. She also plans a complaint against HSBC for closing a personal account of hers.
The FN says Societe Generale closed its accounts earlier this month, and when the central bank ordered a subsidiary, Credit du Nord, to manage an account for the party, the bank refused to process check and credit card payments.
Societe Generale rejected the accusations. "Decisions to open or close a bank account depend purely on banking reasons ... without taking into account any political consideration," it said in a statement.
It added that Credit du Nord offered an FN representative banking services required by law but gave no more details.
HSBC said it complied with all necessary regulations and could not publicly discuss client relationships.
'Thank you and Goodbye'
In France, banks are allowed to close accounts with advance notice and do not have to say why.
Holding an account is a right, however, and a customer can ask the Bank of France to designate a bank that would be forced to open one. But the designated bank can choose to limit the use of the account to basic banking services.
The Bank of France would not comment.
The FN has long said it struggled with financing. It came under scrutiny for a 9 million-euro loan it got in 2014 from a now-defunct Russian bank.
It spent 12.5 million euros ($14.70 million) on the presidential election alone this year. Party supporters have since been asked to lend it money directly.
At her news conference, Le Pen asked party supporters to react to the account closures. Hours later, the hashtag "JeQuitteLaSG," or "I Leave Societe Generale," was the top trending topic on Twitter in France.
Government spokesman Christophe Castaner said the FN should be allowed to have a bank account and use it normally.
"But I do not know why the bank told its client, the National Front, 'Thank you and goodbye,' so I cannot comment on the substance of the case," he told a weekly news conference.
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