U.S. stocks closed the Monday session at record highs ahead of Asia’s Tuesday trading day as investors took bets on a tax plan that would overhaul the U.S. tax system.

Tax reform was the main driving force for optimism in markets stateside. Included in the finalized version of their tax planis a provision to cut the corporate tax rate from 35 percent to 21 percent in 2018, which would likely give corporate profits a boost.

Two holdout Republican senators on Monday confirmed that they would back the tax plan, leaving Sen. Jeff Flake, R-Ariz., the only publicly undeclared GOP senator. With Sen. John McCain fighting brain cancer, the bill will fail in the Senate if two of the remaining 51 Republicans oppose it.

The House is expected to vote on the bill on Tuesday U.S. time.

Major U.S. indexes climbed as the bill moved closer to potentially becoming legislation. The Dow Jones industrial average rose 140.46 points, or 0.57 percent, to its 70th record close this year. The index, which closed at 24,792.2 on Monday, has climbed more than 5,000 points in the year.

Other major indexes also notched record closing highs: The S&P 500 edged up 0.6 percent to close at 2,690.16 and the Nasdaq composite added 0.8 percent to end at 6,994.76.

Despite optimism over the tax plan, the dollar edged lower against a basket of major currencies. The dollar index traded at 93.703 at 6:48 a.m. HK/SIN after trading above the 94 handle earlier in the session.

Against the yen, the dollar was a touch softer at 112.57, near levels seen at the end of last week.

In other news, President Donald Trump on Monday unveiled his national security strategy, which referred to Russia and China as “revisionist powers.” It also noted that those countries were “determined to make economies less free and less fair.”

In Asia, futures pointed to another higher open for Japanese stocks. Nikkei futures traded in Chicago were up 0.47 percent at 23,010 and Osaka futures were 0.17 percent higher at 22,940.

Down Under, the S&P/ASX 200 edged up 0.37 percent in early trade.

On the energy front, oil prices were mixed as markets digested a mix of variables. That included the ongoing Forties Pipeline shutdown in the North Sea and an oil union strike in Nigeria, although Reuters reported that the strike ended within the day.

Brent crude settled 18 cents higher at $63.41 per barrel and U.S. crude futures shed 14 cents to settle at $57.16.

Toyota on Monday announced it intends to offer an electrified version or option for all of its existing Toyota and Lexus models by around 2025. The automaker will begin selling more than 10 electric models from 2020, beginning in China before expanding to more markets.

Meanwhile, a Vietnamese unit of Thai Beverage has won an auction to acquire a 54 stake in Sabeco, Vietnam’s largest brewer, Reuters reported on Monday, citing a source.

The economic calendar for Tuesday is relatively quiet (all times in HK/SIN):

• 8:30 a.m.: Reserve Bank of Australia minutes

— CNBC’s Jacob Pramuk contributed to this report.