France's far-right National Front party, led by Marine Le Pen, says it has borrowed $11 million from a Russian lender.
The French party's treasurer, Wallerand de Saint Just, told RFE/RL that the deal was signed with the Moscow-based First Czech Russian Bank in September.
"We need a lot of money to fund our electoral campaign," he said.
The anti-immigration, Euroskeptic party has been seeking about $50 million to cover its campaign expenses in the 2017 national elections.
Saint Just said the National Front turned to the Russian bank after French and other European banks rejected its loan applications.
He said it had already received the first instalment of $2.4 million from the First Czech Russian Bank.
This is not the first time the National Front has complained of funding difficulties.
According to Saint Just, French banks have been reluctant to lend money to political parties since former President Nicolas Sarkozy was fined more than $620,000 over funding irregularities in his unsuccessful 2012 presidential bid.
The National Front's Russian loan, however, is raising eyebrows.
Le Pen, whose party came first in European elections in May with 25 percent of votes and gained its first parliamentary seats in September, has made no secret of her sympathy for Russian President Vladimir Putin.
She held high-level talks in Moscow in April and has criticized Western sanctions against Russia over its annexation of Crimea and its support for separatists in eastern Ukraine.
Le Pen has also accused EU leaders of waging "a new Cold War" with Russia and slammed French President Francois Hollande's decision to suspend delivery of two Mistral-type warships to Moscow.
Saint Just insisted the deal with the First Czech Russian Bank had "nothing to do with Mr. Putin's politics."
But critics believe the Kremlin is using the National Front as a vehicle to lobby its political interests in France.
"It's very obvious that the National Front is now the instrument of Vladimir Putin's politics in France," says Bernard Grua, a French activist who has actively campaigned against the Mistral sale. "This collusion between the National Front and the Kremlin is extremely detrimental to the values French society is based upon."
According to French investigative media reports, Russian nationalist lawmaker Aleksandr Babakov acted as an intermediary in the National Front loan.
Babakov is one of more than 100 Russian businessman and politicians targeted by EU sanctions.
Saint Just denied ever having dealings with Babakov.
The National Front's treasurer said the party was nonetheless "open to all offers" to cover its remaining campaigning expenses, including further credit lines from Russia.