Russia said on Wednesday it had transferred $650 million worth of bond payments in rubles, raising fresh questions about whether the country is heading for an official default.

The US banned Russia from making dollar debt payments from accounts at American financial institutions on Monday.

Foreign banks refused to process the payment in dollars, which were due Monday, according to Russia's Finance Ministry.

The money was sent to the National Settlement Depository in rubles. The Ministry said it believes its obligations have been fulfilled.

Ratings agencies would consider Russia to be in default if it tried to pay its debts in rubles.

In March, the credit ratings agency said that forced redenomination of payment obligations would indicate that a default or default-like process had begun.

Some of Russia's foreign currency bonds specify that investors can be paid back in rubles in certain circumstances, but the 2022 and 2042 bonds are not among them.

Foreign holders of Russian dollar-denominated bonds signed up to be paid in dollars and global sanctions, so analysts are not sure if they will accept the ruble.

The Monday-night move by the US Treasury was intended to increase economic pressure on Russia. As the US and Europe weighed applying more sanctions to the country, there were reports of possible war crimes.

If Russia can find a way to send dollar payments without using US funds, bondholders can still receive them, according to a person familiar with the Treasury.

The Russian Finance Ministry said the country was not willing to find new ways to send dollars and instead was using its domestic currency.

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