WASHINGTON - A majority of Americans would support US military action against Iran if there were evidence that Tehran is building nuclear weapons, even if such action led to higher gasoline prices, a Reuters/Ipsos polled showed on Tuesday.The poll showed 62 percent of Americans would back Israel taking military action against Iran for the same reasons.US President Barack Obama has said all options are on the table in dealing with Iran's nuclear program. Iran says its nuclear program is peaceful.The Reuters/Ipsos poll showed 56 percent of Americans would support US military action against Iran if there were evidence of a nuclear weapon program. Thirty-nine percent of Americans opposed military strikes.Asked whether they would back US military action if it led to higher gasoline prices, 53 percent of Americans said they would, while 42 percent said they would not.For the first time since early July, more Americans approve of the job Obama is doing than disapprove, according to an additional Reuters/Ipsos poll that shows his approval rating now at 50 percent.The poll, taken March 8-11 on the heels of reports that 227,000 jobs were added to the US economy in February, indicates that Obama's rating has risen by 2 percentage points during the past month. The percentage of Americans who disapprove of the Democratic president was 48 percent, down from 49 percent in February.Some other polls have shown a recent dip in Obama's approval rating, and linked that to rising gasoline prices.But for most Americans, other economic trends during the past month have been relatively positive. Obama appears to be benefiting from that, and perhaps from a bitter Republican presidential campaign that at times has focused on divisive social issues such as abortion."The economy is improving," said Ipsos pollster Cliff Young. "Not by leaps and bounds but people feel that things are getting better."The Ipsos/Reuters poll also found that Americans' confidence in the direction of the country is ticking upward. In the poll, 37 percent of those surveyed said the United States is headed in the right direction, up from 32 percent in February.The Reuters/Ipsos telephone poll of 1,084 adults included 937 registered voters, of whom 554 were Democrats, 421 Republicans, and 109 independentsThe poll's margin of error was plus or minus 3.1 percentage points for all respondents; 3.3 points for registered voters; 4.2 points for Democrats; 4.9 points for Republicans, and 9.8 points for independents.