Fighters aligned with Islamic State said sorry to Israel after firing on its troops, a former Israeli defence minister has revealed.

Moshe Ya'alon was apparently referring to a clash in the Golan Heights - where Israel and Syria have a border - last November in which four fighters from the IS-affiliated Khalid ibn al-Walid Army were killed.

During the attack, IDF soldiers exchanged fire with the terrorist group but the battle was soon over when Israeli tanks and planes crushed the jihadis.

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Not so tough: Former Israeli defence minister said IS-affiliated fighters said sorry after a skirmish in November

According to a German man who visited the Islamic State in 2014, the only country in the world the terrorists fear is Israel. Pictured above, smoke caused by shelling along in the Golan Heights

Speaking to reporters in Afula, northern Israel, the Times of Israel quoted Mr Ya'alon as saying: 'There was one case recently where Daesh [IS] opened fire and apologized.'

He did not expand on his remark and the Israeli army refused to comment.

Under Israeli law, it is technically illegal to communicate with a terrorist group because they are classed as 'enemy agents' - raising questions as to how exactly the apology was delivered.

But a clue might be found in the testimony of Jürgen Todenhöfer, the German man who spent 10 days inside the Islamic State in 2014.

During the fighting in November last year, four fighters from Khalid ibn al-Walid - aligned with Islamic State - were killed by Israeli tanks and planes

He told the Jewish News the only country IS fighters feared is Israel.

'They told me they know the Israeli army is too strong for them,' he said.

He added: 'They are not scared of the British and the Americans, they are scared of the Israelis and told me the Israeli army is the real danger.'

Mr Ya'alon's comment about the apology was related to his country's strategy in the Syrian Civil War.

Israel has adopted a policy of non-intervention in Syrian Civil War, but has defended its borders when fighting spilled over in the past. Above, Islamic State leader Abu Bakr al-Baghdadi adopts an unapologetic stance

Just yesterday Israeli planes bombed an Iranian-supplied arms depot near the Syrian capital, Damascus

They have remained out of the fight for the most part, but have hit back hard when fighting spills into the Israeli Golan Heights - land Israel took from Syria in the 1967 Six-Day War.

Yesterday Israel bombed an Iranian-supplied arms depot near the Syrian capital, Damascus.

Speaking in Moscow on Wednesday, where he was attending a security conference, Israeli Defence Minister Avigdor Lieberman said that Israel 'will not allow Iranian and Hezbollah forces to be amassed on the Golan Heights border'.