Nikkei 225, Nifty 50, CSI 300

Japan’s Nikkei 225 rose over 1% to hit a fresh record high amid mixed trading in the region on Wednesday as investors awaited the Federal Reserve’s interest rate decision, widely believed to bring a second straight 25 basis point cut.

Markets are assigning a nearly 100% probability that another quarter-point reduction, on the heels of September’s cut, would bring the federal funds rate to a range between 3.75%-4.00%.

“If [Fed chair Jerome Powell] comes off dovish, bets for future Fed cuts will increase and provide more fuel to market momentum,” veteran investor Louis Navellier wrote in a daily note.

The federal funds rate, set by the Federal Open Market Committee, is the interest rate banks charge each other for overnight loans. While it doesn’t directly affect consumers, the Fed’s moves often influence borrowing costs for mortgages, credit cards and other loans.

The Topix was flat. South Korea’s Kospi rose 0.17%, while the small-cap Kosdaq lost 0.25%.

Australia’s S&P/ASX 200 lost 0.16%.

Hong Kong markets are closed for the holidays.

Overnight in the U.S., all three major averages closed higher. The S&P 500 rose 0.23% to close at 6,890.89. It had surpassed the 6,900 level for the first time on an intraday basis earlier in the day.

The Nasdaq Composite advanced 0.80% to finish at 23,827.49, while the Dow Jones Industrial Average gained 161.78 points, or 0.34%, to settle at 47,706.37. In addition to their closing highs, the tech-heavy Nasdaq and 30-stock Dow scored new all-time intraday highs alongside the broad market S&P 500.

—CNBC’s Jeff Cox, Sean Conlon and Pia Singh contributed to this report.