Wall Street gained amid optimism that a US-led military strike against Syria might be avoided and as China produced more signs that its economy is gathering steam.
President Barack Obama told ABC News that a US attack "absolutely" would be put on hold if Syrian President Bashar el-Assad would give up the country's chemical weapons.
Even so, "I don't think we would have gotten to this point unless we had maintained a credible possibility for a military strike and I don't think now is the time for us to let up on that," Obama, who is addressing Americans tonight about his plans for Syria, told ABC.
Meanwhile, there was more good news from China, the world's second-largest economy. The nation's industrial output grew 10.4 per cent in August from a year earlier, while retail sales increased 13.4 per cent, according to the National Bureau of Statistics.
In late afternoon trading in New York, the Dow Jones Industrial Average gained 0.7 per cent, the Standard & Poor's 500 Index rose 0.62 per cent, while the Nasdaq Composite Index added 0.49 per cent.
"The news from Syria is positive and we had decent economic data out of China," Gary Flam, a portfolio manager at Bel Air Investment Advisors in Los Angeles, told Bloomberg News.
"Investors came into September cautiously positioned, but one by one their concerns are being removed or lessened."
Shares of General Electric gained, last up 2.2 per cent, propelling the advance in the Dow. Shares of Hewlett-Packard dropped, last 0.8 per cent weaker, and the biggest loser in the Dow today.
Goldman Sachs, Visa and Nike are set to replace Bank of American, Hewlett-Packard and Alcoa in the Dow, S&P Dow Jones said. The changes will take effect on September 23.
Shares of Nike were last up 1.9 per cent, while those of Goldman Sachs were 3.7 per cent stronger, and those of Visa were 2.9 per cent higher.
Shares of Apple declined, last down 1.9 per cent, as the company unveiled its two latest iPhones, including the so-called 5C-model that starts at US$99.
"Apple needs to demonstrate in the coming months that it has other product lines which can start to make up for slowing growth and falling margins in [the] iPhone and iPad," Jan Dawson, a chief telecoms analyst for Ovum Research, told Reuters. "That's a tall order."
In Europe, the Stoxx 600 Index ended the session with a 1.3 per cent increase from the previous close. The UK's FTSE 100 Index rose 0.8 per cent, while France's CAC 40 advanced 1.9 per cent, and Germany's DAX jumped 2.1 per cent.