A military tribunal in Lebanon last month sentenced six men in connection with the murder of Private Rooney and attempted killing of Trooper Shane Kearney, Corporal Joshua Phelan and Trooper Nathan Bryan.

A death sentence was imposed in absentia on the main defendant, Mohammad Ayyad, who remains at large.

However, another man was sentenced to three months’ imprisonment and four others were fined. A seventh defendant was acquitted.

Following representations from the Irish government, the Lebanese government has appointed a new military chief prosecutor who will take over the case.

An appeal against the sentences was yesterday formally lodged with the military Cassation Court.

The Lebanese authorities have also committed to taking urgent steps to ensure the individual convicted of the murder of Private Rooney is taken into custody.

In a statement yesterday, Tánaiste Simon Harris said: “I very much welcome the confirmation today from the Lebanese justice and defence ministers that an appeal has been formally lodged against the sentences handed down in the case of the death Private Seán Rooney and the injuries of his colleagues.

“I have this afternoon spoken with Seán’s mother, Natasha, who I was pleased also to meet last week.

“I informed her of today’s developments and have committed to following up directly with the Lebanese Government in relation to the appeal itself.

“In my calls with my Lebanese counterparts, I made it clear that the sentences handed down in this case are simply not acceptable and are very disappointing.

“They have caused great upset and insult to the Rooney family and everything must be done to ensure justice is served for Seán and his colleagues who were injured.”