The Iran-backed Lebanese group Hezbollah has said US actions in the Red Sea would harm the security of all shipping as the area had now become a conflict zone, saying the Houthis of Yemen would keep up attacks despite US and British strikes.
Hezbollah leader Sayyed Hassan Nasrallah, whose group is a leading part of an Iran-aligned regional alliance which includes the Houthis, said Houthi targeting of ships belonging to Israel or heading to its ports would continue.
"The more dangerous thing is what the Americans did in the Red Sea will harm the security of all maritime navigation, even the ships that are not going to Palestine, even the ships which are not Israeli, even the ships that have nothing to do with the matter because the sea has become a theatre of fighting, missiles, drones and war ships," he said.
"Security has been disrupted," he added.
US and British forces on Friday launched dozens of airstrikes against Houthi forces in retaliation for attacks on Red Sea shipping.
The group says it took the action to support Palestinians under Israeli siege and attack in Gaza.
Washington launched another strike overnight from Friday into Saturday morning.
The Houthis have vowed to retaliate for the attacks.
The Red Sea crisis has fueled fears of a further escalation of the conflict that has rippled around the Middle East since war erupted between the Palestinian group Hamas and Israel on 7 October.
Hezbollah, the Houthis and Iran-backed militias in Iraq have all entered the conflict since then, with Hezbollah firing at Israeli positions along the Lebanese-Israeli frontier, and Iraqi militias firing on US forces in Iraq and Syria.
Mr Nasrallah said envoys sent to Lebanon had been seeking to "extinguish" the Lebanon front by delivering a warning that if the group did not stop its attacks "Israel will launch a war on Lebanon".
He did not identify the envoys.
Mr Nasrallah said the aim of the Lebanon front was to "stop the aggression against Gaza".
The United States should understand "that the security of the Red Sea and calm on Lebanon's front, the situation in Iraq and all developments in the region is tied to one thing: to stop the aggression against Gaza," Mr Nasrallah said.
"You are trying to deal with the consequences and the results, go fix the reason," he added.
Mr Nasrallah was speaking to commemorate the death of a top Hezbollah commander, Wissam Tawil, who was killed in south Lebanon last week, the most senior Hezbollah commander to die in three months of hostilities with Israel.
The war began on 7 October when Hamas fighters attacked Israel, killing 1,200 people and abducting 240 more, according to Israeli tallies.
Since then, nearly 24,000 Palestinians have been killed in Gaza during an Israeli offensive which has laid waste to the territory, according to the toll of the health authorities in Hamas-run Gaza.
The Houthis have also fired drones and missiles up the Red Sea at Israel itself.
Many of the vessels attacked by the Houthis have had no known connection to Israel.
Activist protest
Pro-Palestinian activists have protested at the gates of RAF Akrotiri in Cyprus, angry that the British base was used as a launch pad for strikes against the Houthi militia in Yemen.
US and British warplanes, ships and submarines launched dozens of air strikes against Houthi forces in Yemen overnight on Thursday to Friday.
They were in retaliation for attacks on Red Sea shipping that the Iran-backed group says is a response to the war in Gaza.
RAF Akrotiri was used as a staging point for Typhoon fighter jets involved in the operation.
Several hundred protesters chanted "Out with the Bases of Death" at the entrance to RAF Akrotiri, one of two bases Britain retains in Cyprus, a former colony.
The iron gates to the heavily guarded compound, which sits on a peninsula on Cyprus's southernmost tip, were locked with dozens of police present.
"We are here because we condemn the complicity of the UK government and using Cypriot land for their agenda to support Israel in their onslaught of Gaza," said Natalia Olivia of the Cyprus-based United for Palestine organisation.
Another activist, Nicos Panayiotou, called the use of the British bases a disgrace. "They are using Cypriot land to do something every Cypriot is condemning," he said.
Britain is not obliged to seek permission from Cyprus for operations out of Akrotiri under the terms of the bases' presence on the island.
The strikes have added to concerns that the Israel-Gaza war could spread through the Middle East, with Iran's allies also entering the fray from Lebanon, Syria and Iraq.
Sunday's demonstration was organised before Akrotiri was used for the strikes on Yemen amid perceptions - denied by Britain - that the base is being used to offer logistical support to Israel.
In response to the protests, a British Ministry of Defence spokesperson said: "British Forces Cyprus continue to support the delivery of humanitarian aid into Gaza and no RAF flights into Israel have transported any lethal cargo."
Cameron defends UK actions
Elsewhere, UK Foreign Secretary David Cameron said Britain remains ready to act to "defend freedom of navigation".
"We've demonstrated that we're prepared to follow words and warnings with action and that is incredibly important," Mr Cameron told broadcaster Sky News.
He suggested further strikes could occur if the Houthi rebels, who control much of Yemen, continue to target ships in the Red Sea.
"We have to act. Not acting is also a policy and it was a policy that wasn't working," he said.
He also accused Iran, which backs the Houthis, of being a "malign actor in the region".
Mr Cameron's comments echo those of US President Joe Biden, who said he would "not hesitate to direct further measures to protect our people and the free flow of international commerce as necessary".
Around 12% of global trade normally passes through the Red Sea.
But since mid-November, the attacks have prompted many shipping firms to take the longer route around the tip of Africa, disrupting supply chains and putting upward pressure on inflation.
Read more:
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Mysterious Houthi leader who created a defiant force
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Red Sea: Why it's important to trade and could crisis hike prices?
