US stock indexes traded just below all-time highs on Monday as investors awaited the signing of a preliminary trade deal between the United States and China, as well as the start of the fourth-quarter earnings season.

High-profile technology and internet companies including Apple Inc, Facebook Inc, Microsoft Corp and Inc, which have recently powered Wall Street to all-time highs, boosted the main indexes.

Google-owner Alphabet Inc was on course to become the fourth publicly traded US company to be valued at $US 1 trillion.

An easing of Middle East tensions and signs that the Phase 1 US-China trade agreement will be signed have encouraged buying of risky assets, even though investors know little in the way of details of an agreement expected to be signed in Washington on Wednesday.

“There is some concern about translation of the contract (with China),” said Randy Frederick, vice president of trading and derivatives for Charles Schwab in Austin, Texas.

“The difficulty is we are not going to know anything until Wednesday, but speculation is not enough for markets to go down.”

The other major centrepiece this week will be earnings from the big banks, JPMorgan Chase & Co, Morgan Stanley , Goldman Sachs Group Inc and Wells Fargo & Co , as they kick off the fourth-quarter reporting season from Tuesday.

Analysts expect profits at S&P 500 companies to drop 0.6 per cent for a second straight quarterly decline, according to Refinitiv IBES data.

At 09:59 local time, the Dow Jones Industrial Average was up 61.69 points, or 0.21 per cent, at 28,885.46, the S&P 500 was up 10.44 points, or 0.32 per cent, at 3,275.79 and the Nasdaq Composite was up 43.67 points, or 0.48 per cent, at 9,222.53.

Tesla Inc rose 4.8 per cent after a report said China would not make significant cuts to subsidies for new energy vehicles (NEV) this year. Brokerage Oppenheimer also raised its price target on the automaker.

Shares of Hexcel Corp and Woodward Inc rose 9.5 per cent and 4.8 per cent, respectively, after the two Boeing suppliers said they would combine in an all-stock merger valued at $US 6.43 billion.

Advancing issues outnumbered decliners for a 1.56-to-1 ratio on the NYSE and a 1.30-to-1 ratio on the Nasdaq.

The S&P index recorded 34 new 52-week highs and one new low, while the Nasdaq recorded 81 new highs and 16 new lows.