DUBAI, United Arab Emirates (AP) — Yemen's Houthi rebels warned shippers early Wednesday that “any Israeli vessel” traveling through nearby Mideast waters is now a target as Israel continues to block aid to the Gaza Strip.

The warning from the Houthis again throws into chaos a crucial maritime waterway between Asia and Europe, threatens revenue from Egypt's Suez Canal and possibly will halt aid shipments to war zones. The rebels in the past have also had a loose definition of what constitutes an Israeli ship, meaning other vessels could be targeted as well.

The statement from the Houthis' Humanitarian Operations Coordination Center follows a four-day deadline set by the rebels for Israel to resume aid shipments.

“We hope it is understood that the actions taken by the (Houthi military) ... stem from a deep sense of religious, humanitarian and moral responsibility toward the oppressed Palestinian people and aim to pressure the Israeli usurper entity to reopen the crossings to the Gaza Strip and allow the entry of aid, including food and medical supplies,” the statement said.

It described the warning as taking hold in the Red Sea, the Gulf of Aden, the Bab el-Mandeb Strait and the Arabian Sea.

The statement added: “Any Israeli vessel attempting to violate this ban will be subject to military targeting in the declared operational area.”

There was no immediate sign of an attack on ships. Israel's military did not respond to an immediate request for comment.

The maritime security firm Ambrey warned the statements from the Houthis were “ambiguous,” likely putting more ships at risk.

It's “likely to have extended once more toward ships partially owned by Israeli individuals or entities, vessels managed and/or operated by Israeli individuals or entities, vessels heading to Israel and to ships of companies that call Israel,” the firm said.

There was no direct threat made against the U.S. Navy, whose Bahrain-based 5th Fleet patrols the Mideast. However, the earlier Houthi campaign saw American and Western warships repeatedly targeted. The aircraft carrier USS Harry S. Truman and other ships associated with its carrier group are operating in the Red Sea now.

The rebels’ secretive leader, Abdul-Malik al-Houthi, warned Friday that attacks against Israel-linked vessels would resume within four days if Israel didn’t let aid into Gaza. That deadline passed Tuesday.

The rebels had targeted over 100 merchant vessels with missiles and drones, sinking two vessels and killing four sailors during their campaign targeting ships from November 2023 until January of this year.

The attacks greatly raised the Houthis' profile as they faced economic problems and launched a crackdown targeting any dissent and aid workers at home amid Yemen's decadelong stalemated war that's torn apart the Arab world's poorest nation.