President Donald Trump on Wednesday proposed slashing the US tax rate on corporate and pass-through business profits to 15 percent from 35 percent or more.

The administration is determined to get the tax reform done by this year, Treasury Secretary Steven Mnuchin said at press conference.

The promise of a massive tax cut has been at the core of the post-election rally, which has driven Wall Street's indexes to record highs. However, the rally has stalled of late due to a lack of clarity on Trump's policies and the failure of his healthcare reform bill.

At 13:48 p.m. ET (1748 GMT), the Dow Jones industrial average was up 38.02 points, or 0.18 percent, at 21,034.14, the S&P 500 was up 5.06 points, or 0.21 percent, at 2,393.67 and the Nasdaq Composite was up 6.52 points, or 0.11 percent, at 6,032.01.

Six of the 11 major S&P sectors were higher.

Among stocks, United Technologies rose 1.8 percent and provided the biggest boost to the Dow, after reporting a quarterly profit that beat expectations.

On the flip side, Boeing shares fell about 1 percent and weighed on the Dow after the planemaker reported a decline in revenue.

Procter & Gamble declined 2 percent after reporting lower quarterly profit.

Advancing issues outnumbered decliners on the NYSE by 1,859 to 1,036, for a 1.79-to-1 ratio on the upside. On the Nasdaq, 1,790 issues rose and 1,005 fell for a 1.78-to-1 ratio favoring advancers.

The S&P 500 index showed 77 new 52-week highs and 2 new lows, while the Nasdaq recorded 194 new highs and 19 new lows.