Japan"s Nikkei inched down ahead of a crucial policy decision by the U.S. Federal Reserve on Wednesday, with declines in shipping stocks outweighing gains in carmaker Toyota (7203.T) and its group companies. The broad Topix index (.TOPX), however, posted a 0.37% gain at the midday break, with eight shares advancing for every five that sank. The Nikkei share average (.N225) slipped 0.08%, giving up earlier gains. Investors expect the U.S. Federal Open Market Committee (FOMC) to adopt a more hawkish tone at the conclusion of their two-day meeting, quickening the pace at which they taper bond-buying stimulus and potentially setting up earlier interest rate hikes. read more "Position adjustments before the FOMC are center stage, and it"s not possible to discern a direction to the market amid that," said Hajime Sakai, the chief fund manager at Mito Securities Co in Tokyo. Toyota (7203.T) was the second-best performer among the 30 core Topix names, notching a 2.69% gain after Japan"s biggest automaker said on Tuesday it would commit about $70 billion to electrify its lineup by 2030. read more That also lifted its group companies, with Toyota Tsusho (8015.T) and Denso (6902.T) jumping 4.20% and 4.31%, respectively. Transport equipment (.ITEQP.T) was the Topix"s best performing sector, adding 1.99%. Among other notable gainers, Recruit Holdings (6098.T) and SoftBank Group (9984.T) rose 2.97% and 2.14%, respectively, as they rebounded following recent slides. Sony (6758.T) advanced 1.93%. At the other end, sea transport"s (.ISHIP.T) 3.97% tumble made it the worst-performing Topix sector by a wide margin. Reporting by Tokyo markets team; Editing by Devika Syamnath Our Standards: The Thomson Reuters Trust Principles.