LONDON (Reuters) – U.S. sanctions on two units of Chinese shipper COSCO hit the liquefied natural gas (LNG) tanker industry on Monday as U.S.-listed Teekay LNG (TGP.N) said its joint venture in Russia had been “blocked” for its ties to COSCO.

The United States imposed sanctions on the two units – COSCO Shipping Tanker (Dalian) Co, Ltd and its subsidiary COSCO Shipping Tanker (Dalian) Seaman & Ship Management Co, Ltd – for allegedly carrying Iranian crude oil.

Teekay LNG said on Monday its 50-50 Yamal LNG Joint Venture had been deemed a “blocked person” under the sanctions as its partner China LNG Shipping (Holding) Limited (CLNG) is 50% owned by COSCO Dalian.

“As a result of CLNG’s 50% interest, the Yamal LNG Joint Venture also currently qualifies as a “Blocked Person” under OFAC rules,” Teekay said in a statement, referring to the Executive Office of Foreign Assets Control (OFAC) Order.

The venture owns four operational Arc7 ice-breaking tankers – the Eduard Toll, Rudolf Samoylovich, Nikolay Yevgenov and Vladimir Voronin – which carry gas from the massive Yamal LNG production facility in the Russian Arctic.

Yamal LNG is operated by Russian independent gas producer Novatek (NVTK.MM).

A fifth Teekay Arc7 tanker, the Georgiy Ushakov, is heading to Yamal, having been built and tested over the summer around South Korea’s Daewoo Shipbuilding and Marine Engineering (DSME) (042660.KS) shipyard. A sixth, Yakov Gakkel, is undergoing sea trials.

A Novatek spokeswoman declined to comment immediately.

Due to the Arctic conditions, the ice-breaking ARC7s are critical for carrying LNG produced at Yamal westwards to Europe and eastwards to Asia.

There are currently 14 such tankers in operation with Dynagas (DLNG.N), Sovcomflot and Mitsui OSK Lines (9104.T) owning the others.