DUBAI (Reuters) - Iran will support Palestinian armed groups as much as it can, Iran's Supreme Leader Ayatollah Ali Khamenei said on Wednesday, urging Palestinians to confront a U.S. plan for Israeli-Palestinian peace.

"We believe that Palestinian armed organizations will stand and continue resistance and the Islamic Republic sees supporting Palestinian groups as its duty," Khamenei said in a speech carried on his website.

"So it will support them however it can and as much as it can and this support is the desire of the Islamic system and the Iranian nation."

U.S. President Donald Trump announced a U.S. plan last month which would set up a Palestinian state with strict conditions but allow Israel to take over long-contested Jewish settlements in the occupied West Bank.

Palestinian leaders have rejected it as biased toward Israel.

Trump's plan is to the detriment of America and Palestinians should confront the deal by forcing Israelis and Americans out through jihad, Khamenei said, according to his official website.

Tensions have spiked between Iran and the United States after top Iranian military commander Qassem Soleimani was killed in a U.S. drone strike in Baghdad on Jan. 3, prompting the Islamic Republic to retaliate with a missile attack against a U.S. base in Iraq days later.