U.S. President Barack Obama left here Monday for a three-day bus tour through the Midwest to discuss ways of economic growth, as his approval rating hit all-time low in a new poll.

According to the White House, the tour would start in Minnesota, followed by stops in Iowa and Illinois, an opportunity for the president to temporarily leave Washington politics behind and venture into the country's heartland.

Obama was grounded in the capital for much of the past month due to the prolonged debt-ceiling debates between Democrats and Republicans.

The toll of the stand-off was evident in a Gallup Poll released Sunday, which showed Obama's approval rating hit an all-time low.

In the Gallup survey conducted on Thursday through Saturday, 39 percent of Americans said they approved of the way Obama was handling his job as president, against 54 percent who disapproved of the president's job performance.