U.S. stocks opened on Thursday after the United States delayed scheduled tariff hikes on billions worth of Chinese imports, and the European Central Bank cut interest rates in an effort to boost euro zone economic growth.
"Markets are still on the trade war seesaw today", said David Carter, chief investment officer at Lenox Wealth Advisors in NY.
The S&P 500 gained 12 points, or 0.4%, to 3,013.
The Dow Jones Industrial Average .DJI rose 45.41 points, or 0.17%, to 27,182.45, the S&P 500 .SPX gained 8.64 points, or 0.29%, to 3,009.57 and the Nasdaq Composite .IXIC added 24.79 points, or 0.3%, to 8,194.47.
The decision comes after China extended an olive branch by exempting some US anti-cancer drugs and other goods from additional tariffs, ahead of planned high-level trade negotiations.
Semiconductor companies, whose revenues primarily rely on trade with China, also extended mild gains, as the Philadelphia Semiconductor Index edged higher by almost 0.3 percent around the closing bell.
The U.S. -China talks have basically gone nowhere since early May, when the two sides appeared to be nearing a deal. As the series of data including trade and the latest PPI numbers had shown, China's economic conditions had continued to trend downwards to reflect the deterioration.
Export-driven Asian currencies from Taiwan to Australia rallied on the buoyant mood as the world's two largest economies each granted concessions in their heated tariff dispute.
Google parent Alphabet Inc (GOOGL.O) shares rose 1.5% after Google reached a $1.1 billon settlement with French authorities to resolve a fiscal fraud probe, and following a legal victory over German publishers over fee demands.
The S&P index recorded 39 new 52-week highs and one new low, while the Nasdaq recorded 79 new highs and 20 new lows.
Benchmark 10-year notes US10YT=RR last fell 13/32 in price to yield 1.7785%, from 1.733% late on Wednesday. UnitedHealth Group fell 1.8%.
The yield on benchmark 10-year Treasury notes rose to 1.7730%, the highest in five weeks, extending a sell-off in government bonds that started on September 4.
Investors gave a cool reception to SmileDirectClub's stock market debut.
After a hard August in which concerns about a global recession sparked a scramble into safer assets, investors have been returning to riskier markets this month, encouraged by China and the United States making moves to ease trade tensions and by receding fears of a no-deal Brexit.
Benchmark crude oil fell 66 cents to settle at $55.09 a barrel. Gold futures shot up to trade 1% higher at $1,518.30 per ounce.
Oil prices rose in Asia, rebounding from a tumble on Wednesday, on hopes OPEC members will cut output to support prices. The euro strengthened to $1.1073 from $1.1007.
Sterling traded at $1.2328, little changed following a 0.24% decline on Wednesday after a Scottish court ruled that Prime Minister Boris Johnson's suspension of the British Parliament was unlawful.