(For a Reuters live blog on U.S., UK and European stock markets, click LIVE/ or type LIVE/ in a news window) * Indexes up: Dow 0.68%, S&P 0.77%, Nasdaq 0.92% (Adds comment, details; updates prices) Aug 27 (Reuters) - The S&P 500 and the Nasdaq hit record highs on Friday as Federal Reserve Chair Jerome Powell signaled the U.S. central bank will remain patient as it tries to nurse the economy back to full employment. In prepared remarks for a speech to the Jackson Hole economic conference, Powell said discussions about exactly when to begin reducing the $120 billion bond-buying program remain unresolved, and must be squared against the health and economic risks posed by the highly contagious Delta coronavirus strain. “Even though a lot of the other Fed presidents have come out and said ‘we’re going to do this sooner rather than later’, prudent Powell is going to make sure that the economy really is healed,” said Kim Forrest, chief investment officer at Bokeh Capital Partners in Pittsburgh. “You don’t want to make people carsick when you’re driving an economy.” All the 11 major S&P sectors were up, with energy, materials and communication services jumping 1% each. U.S. stocks had fallen from all-time highs on Thursday on concerns over developments in Afghanistan and hawkish signals from Fed officials. The three major indexes were set for weekly gains, with the tech-heavy Nasdaq looking to outperform the S&P 500 and the blue-chip Dow. At 10:21 a.m. ET, the Dow Jones Industrial Average was up 239.76 points, or 0.68%, at 35,452.88, the S&P 500 was up 34.50 points, or 0.77%, at 4,504.50, and the Nasdaq Composite was up 137.84 points, or 0.92%, at 15,083.65. Among earnings-driven moves, apparel retailer Gap Inc jumped 3.7% after it raised its full-year net sales forecast as socializing makes a comeback with easing pandemic curbs. Advancing issues outnumbered decliners by a 4.50-to-1 ratio on the NYSE and a 3.29-to-1 ratio on the Nasdaq. The S&P index recorded 46 new 52-week highs and one new low, while the Nasdaq recorded 72 new highs and 25 new lows. (Reporting by Devik Jain in Bengaluru; Editing by Saumyadeb Chakrabarty) Our Standards: The Thomson Reuters Trust Principles.