* Materials set for best day since July
* DuPont rises on profit beat
* Automakers rise after Trump meeting
* Indexes up: Dow 0.46 pct, S&P 0.44 pct, Nasdaq 0.42 pct (Updates to early afternoon)
By Yashaswini Swamynathan
Jan 24 (Reuters) - The S&P 500 and the Dow were set for their best day in three weeks on Tuesday, powered by technology and bank stocks.
Investors are also assessing quarterly earnings report, while seeking more clarity on President Donald Trump's economic policies.
"We are now in a phase where the policies need to come to fruition to justify the move we have seen in the post-election period," said Bill Northey, chief investment officer at Private Client Group of U.S. Bank.
"I believe that the market's focus has shifted a bit back to fundamentals and the fourth-quarter earnings season, which at this point has started off on a reasonably positive note."
Profits of S&P 500 companies are estimated to have risen 6.6 percent in the latest quarter - marking the strongest growth in three years, according to Thomson Reuters I/B/E/S.
However, the Trump rally has contributed to somewhat lofty valuations. The S&P 500 is trading at 17.7 times forward 12-month earnings, compared with the 10-year median of 14.7.
Speaking to chief executives of General Motors, Ford and Fiat Chrysler, Trump said he wanted to see new auto plants built in the United States, while reiterating his plans to cut taxes and regulations.
GM and Ford's stocks rose more than 1.5 percent, while Fiat Chrysler was up 6.2 percent.
At 12:37 p.m. ET (1737 GMT), the Dow Jones Industrial Average was up 91.07 points, or 0.46 percent, at 19,890.92.
The S&P 500 was up 10.01 points, or 0.44 percent, at 2,275.21 - about 5 points away from its all-time high.
The Nasdaq Composite was up 23.24 points, or 0.42 percent, at 5,576.18, after coming as close as 6 points of its record high.
Eight of the 11 major S&P sectors were higher, driven by a 0.7 percent rise in technology and a 1.13 percent gain in financials.
Materials jumped more than 2 percent and were on track for their best day since July. The sector was bolstered by a 4.2 percent rise in DuPont, which reported a better-than-expected quarterly profit.
Energy index was up more than 1 percent as oil prices rose
Verizon, 3M, Travelers and Johnson & Johnson - the other four Dow components that reported results earlier in the day - were trading lower.
IBM was the top stock on the S&P 500, rising 2.7 percent.
Yahoo rose 3.3 percent after the company reported better-than-expected quarterly profit and revenue and said the sale of its core internet business to Verizon should be completed in the second quarter.
Advancing issues outnumbered decliners on the NYSE by 2,073 to 778. On the Nasdaq, 1,732 issues rose and 1,007 fell.
The S&P 500 index showed 33 new 52-week highs and two new lows, while the Nasdaq recorded 78 new highs and 27 new lows. (Reporting by Yashaswini Swamynathan in Bengaluru; Editing by Anil D'Silva)