YEMEN’S Houthi-led government warned today that “any Israeli vessel” sailing through nearby waters could be targeted as Israel continues to block aid to the Gaza Strip.

The threat raises the prospect of renewed disruption to a key sea route between Asia and Europe. The Houthis have used a loose definition of what constitutes an Israeli ship, so other vessels could be targeted as well.

The statement from Yemen’s Humanitarian Operations Co-ordination Centre follows the setting of a four-day deadline for Israel to resume aid shipments into the besieged and war-shattered Gaza Strip.

“We hope it is understood that the actions taken by the Yemeni 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 applying to 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.”

Israel’s military did not respond to a request for comment.

Earlier this month, Israel halted all aid deliveries to the Gaza Strip and has warned of “additional consequences” for Hamas if the fragile truce in the war isn’t extended as negotiations continue over starting a second phase of the ceasefire.

The move drew intense international criticism as, even before the war, the over two million Palestinians living in Gaza relied on international aid, a need that has only intensified after a grinding Israeli military offensive caused massive destruction in the coastal enclave.

Meanwhile, in the United States, protests in support of the Palestinians have led to a crackdown by the authorities.

Mahmoud Khalil, a permanent US resident and recent graduate of Columbia University, was arrested on Tuesday after a direct intervention by US Secretary of State Marco Rubio.

Amnesty International USA executive director Paul O’Brien said the arrest ”sends a chilling message to people across this country, on and off campuses, that anyone exercising their rights will be subject to repression, detention and possible deportation.”

“The US government must release Mahmoud Khalil immediately,” he added.

In an open letter, academics, artists, trade union leaders and activists also joined the call for Mr Khalil’s release and for the protection of free speech on campuses.

The signatories included actor Susan Sarandon, scholar Professor Robin DG Kelley, writer and activist Vijay Prashad, Answer Coalition national director Brian Becker and dozens of union leaders.