Most stock markets in the Gulf fell in early trade on Tuesday, in line with oil prices and Asian shares as the spread of the Omicron coronavirus variant rattled investors. Britain and Norway joined a slew of governments around the world which are tightening restrictions to stop the spread of the Omicron variant. read more At least one person has died in the United Kingdom after contracting the Omicron coronavirus variant, Prime Minister Boris Johnson said on Monday, the first publicly confirmed death globally from the swiftly spreading strain. read more Saudi Arabia"s benchmark stock index (.TASI) eased 0.2%, with Banque Saudi Fransi (1050.SE) losing 1.2% and Sahara International Petrochemical Company (2310.SE) retreating 1.1%. Oil prices, a key catalyst for the Gulf"s financial markets, fell due to investor worries about demand after restrictions were imposed in Europe and Asia amid a rise in coronavirus cases. However, the Organization of the Petroleum Exporting Countries on Monday raised its world oil demand forecast for the first quarter of 2022 and stuck to its timeline for a return to pre-pandemic levels of oil use, saying the Omicron coronavirus variant would have a mild and brief impact. read more Dubai"s main share index (.DFMGI) declined 0.5%, weighed down by a 0.9% fall in sharia-compliant lender Dubai Islamic Bank (DISB.DU) and a 0.4% decrease in top lender Emirates NBD (ENBD.DU). In Abu Dhabi, the index (.ADI) dropped 0.8%, dragged down by a 0.8% drop in Alpha Dhabi Holding (ALPHADHABI.AD). The Qatari benchmark (.QSI) lost 0.3%, with the Gulf"s biggest lender Qatar National Bank (QNBK.QA) falling 0.8%. Reporting by Ateeq Shariff in Bengaluru; Editing by Subhranshu Sahu Our Standards: The Thomson Reuters Trust Principles.