The United States has warned Turkey in recent days about the export to Russia of chemicals, microchips, and other products that can be used in Moscow's war effort in Ukraine, and it could move to enforce existing bans, according to a senior U.S. official. Brian Nelson, the U.S. Treasury Department's top sanctions official, visited Turkish government and private-sector officials on February 2-3 to urge more cooperation in disrupting the flow of such goods, the official said, requesting anonymity to discuss the talks. To read the original story by Reuters, click here.