The US dollar climbed against the yen and the euro during foreign exchange trading this morning (September 21st), bolstered by speculation that the Federal Reserve will begin scaling back its fiscal stimulus programme.Ahead of the opening of the G20 Summit in Pittsburgh later today, the greenback rose against 13 of the 16 counterparts tracked by Bloomberg, with the currency hitting a two-week high against sterling and a one-week high against the yen.Joseph Capurso, a currency strategist in Sydney at Commonwealth Bank of Australia, said that foreign exchange traders are expectant that the Federal Open Market Committee will begin to remove some of the fiscal instruments put in place to shore up the national economy during the economic crisis."The catalyst for the dollar strengthening on a sustained basis is likely to come from the FOMC," he said.In the wake of the crisis, the dollar has tended to climb on the back on the back of gloomy economic data as foreign exchange traders flock to safe-haven, low-yield currencies to mitigate risk.