“In the event of any foreign party insisting on hostilities against, an assault on, or military or security intervention in Yemen, then Islam requires all its followers to pursue jihad,” a statement signed by 150 clerics on Thursday said.

Foreign governments have voiced increasing concern about the situation in Yemen since an attempted attack on a US-bound airliner, after which al-Qaeda in the Arabian Peninsula claimed it had armed the alleged bomber.

On Wednesday, Carl Levin, the chairman of the US senate armed services committee, said that Washington should use drone attacks, air raids or covert operations against al-Qaeda fighters in the country.

“Most options ought to be on the table,” short of invasion by US forces, the Democrat senator said.

The US and Britain have announced plans to fund Yemen’s counterterrorism police force, but Barack Obama, the US president, has explicitly ruled out sending in troops.

Relatives of Massoud Ali Mohammadi were accompanied by members of Iran’s Revolutionary Guards as they carried his body from his house to a nearby shrine on Thursday.

Some of the mourners shouted slogans such as “Death to Israel” and “Death to America” while the semi-official Fars news agency said some people carried green banners in a show of support for the opposition.

Neither the police nor the intelligence services have yet reported any leads in their investigation of the explosion which killed Ali Mohammadi outside his home in north Tehran on Tuesday.

Senior Iranian officials have blamed the remote-controlled blast on an exile opposition group they claim has ties to the US and Israel.

‘Terrorist act’

Mohammad Khatami and Hashemi Rafsanjani, both former Iranian presidents, condemned the attack in separate statements on Wednesday.

They did not directly accuse any group of the killing, but each honoured Ali Mohammadi – a 50-year-old researcher and lecturer in quantum physics - as a victim of terrorism.

The incident occurred about 30km from the Allenby Bridge that links Jordan and the Israeli occupied Palestinian West Bank at about 5pm (1500GMT) on Thursday, Israeli army radio said.

Danny Nevo, Israel’s ambassador to Jordan, was not in the convoy that was travelling from Amman, the Jordanian capital, Israeli officials said.

There was no immediate claim of responsibility.

“While cars, including two Israeli Embassy cars, were travelling near the town of Naur on the road between Amman and the Jordan Valley a bomb exploded without causing casualties or damage,” Nabil Sharif, the information minister, said.

“The cars were not damaged by the blast.”

Jordanian officials said that they were investigating the incident.

Neighbourly relations

Al Jazeera’s Nisreen al-Shamyleh, reporting from the site of the attacks, said: “This took place near the King Hussein Bridge, also called Allenby in Israel, on the Jordanian side.

“Right now security is heavy in this area.

“Security personnel and police are on the road trying to identify the explosive material. There is some damage to the road.”

Al-Shamyleh said it could have implications for relations between the two nations if it was found that the Israeli convoy was the target of the attack.

“What it means is diplomats are being watched. People know their movements and to a certain extent know how to target them. So it has implications for Israeli diplomats’ safety,” she said.

Al-Shamyleh added that it was unknown what kind of explosives or bomb was used as yet.

Palestinian sympathy

Jordan signed a peace treaty with Israel in 1994 – the second Arab state to do so after Egypt.

However, the treaty is widely rejected by the Jordanian population. Up to 60 per cent of Jordan’s population is of Palestinian origin.

Jacky Rowland, Al Jazeera’s correspondent in Jerusalem, said: “Relations have been cool at best, hostile at worst since the peace treaty was signed just over 15 years ago.

“Obviously there is a lot of sympathy and empathy in Jordan with the Palestinian people in the occupied territories.

“I think the point at which relations really started to cool was as people in Jordan really saw that no progress was being made in efforts to have a peace treaty between Israel and Palestinians.

“Then, relations hit an all-time low with the Israeli crackdown on the Palestinian uprising which began in 2000, and since then the Israeli seige on Gaza and the war on Gaza just over year ago.

“In a recent opinion poll in Jordan not a single person interviewed gave Israel a favourable rating or said they were willing to accept Israel or engage with it in any way.”

The Allenby/King Hussein Bridge is 50km west of Amman.

Danny Ayalon, Israel’s deputy foreign minister, embarrassed Oguz Celikkol, the Turkish envoy, on Monday, making him sit on a low couch and removing the Turkish flag from the table in a meeting called to convey Israeli protests over a Turkish television series.

A statement from the office of the Israeli prime minister on Wednesday said: “Prime minister [Binyamin] Netanyahu, together with foreign minister Avigdor Lieberman co-ordinated the apology letter sent by deputy foreign minister Ayalon to the Turkish ambassador and hopes this would end the affair.”

Recep Tayyip Erdogan, Turkey’s prime minister, said that his country had received the apology it “wanted and expected” from Israel over the dressing down of its ambassador.

“I was told that we received the response that we wanted and expected in diplomatic terms,” Erdogan told reporters at the airport after returning from a visit to Russia.

“The letter includes an expression of apology,” he said.

Ambassador threat

Abdullah Gul, the Turkish president, deemed an earlier Israeli apology on Wednesday as insufficient and threatened to recall his ambassador unless a formal apology was made by the end of the day.

“Unless they make up for it by this evening, our ambassador will return on the first plane tomorrow to hold consultations,” Abdullah Gul, the Turkish president, was quoted as saying by the country’s NTV news channel.

After Wednesday’s official apology, Netanyahu “again expressed his concern over the cooling of the ties between Israel and Turkey” and instructed officials “to find ways to prevent this trend,” the statement from his office said.

The series that sparked the latest row between the two countries was a Turkish television drama, called The Valley of the Wolves, which Israel says depicts Israeli security forces as kidnapping children and shooting old men.

That followed a drama aired on Turkish state television last October that appeared to portray Israeli soldiers shooting a Palestinian baby at close range.

Ayalon had summoned Celikkol on Monday to express Israel’s displeasure over The Valley of the Wolves.

At the beginning of the conversation with the Turkish envoy, the deputy foreign minister told cameramen in Hebrew: “Pay attention that he is sitting in a lower chair … that there is only an Israeli flag on the table and that we are not smiling.”

The row came ahead of a planned visit by Ehud Barak, the Israeli defence minister, to Turkey on Sunday.

That military assault left hundreds dead and damaged millions of dollars worth of infrastructure.

The delegation, organised by the European Campaign to End the Siege on Gaza (ECESG), is due to arrive in Egypt on Thursday, from where they will cross into Gaza.

The delegation, headed by Sir Gerald Kaufman, a veteran British MP, is the biggest in years to visit Gaza.

The parliamentarians represent 12 European countries and include Lord Ahmed, Jeremy Corbyn, Baroness Tonge and Clare Short, a former UK international development secretary.