Iranian President Mahmoud Ahmadinejad dismissed the latest U.N. sanctions against Iran, saying the new sanctions are "like a used tissue."

"We do not recognize sanctions," the hard-line leader said.

Ahmadinejad made the comments after a U.N. Security Council resolution imposing a fourth round of penalties against Iran.

He added "from right and from left, they adopt sanctions, but for us they are annoying flies, like a used tissue."

The sanctions target Iran's powerful Revolutionary Guard, ballistic missiles and nuclear-related investments.

Some experts have said the new sanctions are not tough enough to change Iran's behavior. President Barack Obama disagreed.

"These sanctions show the united view of the international community that a nuclear arms race in the Middle East is in nobody's interest," Obama said.

The big question now is whether the new sanctions will somehow persuade Tehran to suspend its fast-expanding nuclear program.