Selim Idriss, the military chief of the rebel Free Syrian Army, will travel to Washington Saturday, a report said.
The Now Lebanon website did not provide further details.
The US has said it would arm the rebels after it concluded Syrian forces under President Bashar al-Assad were using chemical weapons.
US President Barack Obama has decided to provide "direct military support" to the opposition, his national security adviser Ben Rhodes said.
Rhodes did not specify whether the support would include lethal aid, such as weapons, which would mark a reversal of Obama's resistance to arming the rebels.
Idriss welcomed the news.
"We hope that such a move will not be ink on paper, but will be implemented on the ground as soon as possible," he told Al Arabiya TV channel.
meanwhile, the acting head of the Syrian National Coalition, George Sabra, described the decision as "a positive step" and expressed hope that there would be no delay.
In a statement Friday, Syria's foreign ministry dismissed the chemical weapons claims by the US intelligence as "a pack of lies".
In a tweet, Alexei Pushkov, chairman of the Russian parliament's foreign relations committee, also accused the US of "fabricating" evidence of chemical weapons use to step up its military involvement in Syria.