MOSCOW, Sept 26 (Reuters) - The impending expiry of a

U.S. licence permitting transactions involving the pillars of

Russia's financial infrastructure could make it harder and

costlier for Russian businesses to deal in Chinese yuan, sources

engaged in imports and payments told Reuters.

The yuan, which hit a near-one-year high against the rouble

on Wednesday, has become the most traded foreign currency in

Moscow since Russia's decision to send troops into Ukraine in

February 2022 sparked sweeping Western sanctions and a

ramping-up of Russia's de-dollarisation policy.

With Chinese banks wary of the secondary sanctions risks of

dealing with Russian entities blacklisted by Washington, and the

Bank of Russia reluctant to continue pumping in yuan liquidity

through FX swaps, some importers fear that payment issues

between Russia and China could worsen.

"The situation may change after Oct. 12," a person engaged

in importing told Reuters. "An abrupt shortage of yuan or a

complete refusal to accept payments from Russia by Chinese banks

is possible."

YUAN LIQUIDITY SHORTAGE

The U.S. Treasury's Office of Foreign Assets Control (OFAC)

in June imposed sanctions on Moscow Exchange and its

clearing agent, the National Clearing Centre (NCC), leading to

an immediate trading halt in dollars and euros on Russia's

largest bourse.

OFAC issued a licence, due to expire on Oct. 12, authorising

the winding down of certain transactions. OFAC did not respond

to a request for comment when asked whether another extension to

the licence was possible.

Upon expiry, all conversion operations, including for

Chinese banks' subsidiaries, will halt and all open FX positions

through Moscow Exchange will be closed and stopped, a person in

the payments market said.

"Accordingly, the situation with the supply of yuan

liquidity will become even more difficult," the person said.

Payments worth billions of yuan are being held up as Chinese

state banks shut down transactions with Russia, Reuters reported

last month, while many transactions face lengthy delays,

increased logistics costs and higher agents' fees.

Complicating things, the Russian unit of Austria's

Raiffeisen Bank International has refused to make

payments to China since September, a person familiar with the

matter said.

RBI declined to comment.

SYSTEMIC RISK

The central bank has acknowledged the payment issues and

urged commercial lenders to reduce their yuan loan portfolios as

this exacerbates the yuan liquidity shortage by forcing the

central bank to replenish short-term yuan stocks and driving up

the swap interest rate and market volatility.

"The central bank is trying to somehow stop the shortage of

yuan, as swap rates ... last week reached up to 120%," said

Finam brokerage analyst Alexander Potavin, describing the risk

as systemic for the largest Russian companies.

Central bank data shows banks have cut swap borrowings, to

15.4 billion yuan ($2.19 billion) on Wednesday from a peak of

35.2 billion yuan in early September.

"If yuan trading on Moscow Exchange is really cancelled,

then there will be no exchange benchmark for the rouble," said

Potavin. "Yuan quotes will be formed on the results of trades on

the interbank market, which is absolutely non-transparent,

manipulable and volatile."

($1 = 7.0184 Chinese yuan renminbi)