Oil shipping rates continue to rise due to expectations of tighter global tanker supply from U.S. sanctions on Russia's fleet and increased demand for ships to load Middle East oil for Asia. Shell and Shenghong Petrochemical have booked VLCCs to load Middle East crude in early February, driving up rates. Traders are expected to seek more tankers to load crude from Saudi Arabia in February, potentially driving freight rates even higher. Surging freight costs and spot premiums for Middle East crude are putting pressure on Asian refiners' margins.