TEHRAN, March 21 (Xinhua) -- Iran's Supreme Leader Ali Khamenei warned here on Friday that the United States and its allies will receive a "hard slap" if they use threats when dealing with Iran.

"The Americans should know that, when dealing with Iran, they will get nowhere with threats. They and the others should know that if they take any malicious action against the Iranian nation, they will receive a hard slap," Khamenei said during a meeting with people from different walks of life in the country.

The U.S. and European allegation that resistance groups in the West Asia region are Iran's proxies was a "big mistake and an insult to these groups," he said, noting that Iran does not need any proxy.

He called for opposing and resisting Israel's "malicious acts" in any way possible.

Khamenei's remarks came after U.S. President Donald Trump recently accused Iran of "still sending large levels of supplies" to the Houthi armed group in Yemen, and promised to hold Iran "fully accountable" for Houthi actions.

Last week, the Houthi group said it would resume attacks on Israeli ships in the Red Sea, Arabian Sea, Gulf of Aden, and Bab al-Mandab Strait until crossings into Gaza are reopened and humanitarian aid is allowed in.

On Saturday, the United States renewed airstrikes on Yemen, after Trump vowed a continued crackdown on the Houthi group until it ends attacks on Red Sea shipping.

On Tuesday, Israel resumed strikes in Gaza after its ceasefire deal with Hamas that began on Jan. 19 unraveled. Israeli troops later launched ground operations in southern, northern, and central Gaza.

In response, the Houthis threatened on Tuesday to "resume escalation at its highest levels" against Israel if the renewed Israeli assault on Gaza does not stop. The group has subsequently launched new attacks on Israeli and U.S. targets.