Israeli security forces backed by helicopters raided the volatile West Bank city of Jenin on Tuesday, killing at least nine Palestinians in what Prime Minister Benjamin Netanyahu called a "large-scale and significant military operation."

The action, launched a day after U.S. President Donald Trump declared he was lifting sanctions on ultranationalist Israeli settlers who attacked Palestinian villages, was announced by Netanyahu as a new offensive against Iranian-backed militants.

"We are acting systematically and resolutely against the Iranian axis wherever it extends its arms — in Gaza, Lebanon, Syria, Yemen and Judea and Samaria," Netanyahu said. Judea and Samaria are terms Israel uses for the occupied West Bank.