An Egyptian court has slapped Abdullah Mursi, the youngest son of ousted president Mohammad Mursi, along with a friend, with one year in jail for illegal drug possession.

An Egyptian court has slapped Abdullah Mursi, the youngest son of ousted president Mohammad Mursi, along with a friend, with one year in jail for illegal drug possession.

"We will appeal the verdict," Abdullah's lawyer, Mohamed Saber, told media outlets on Wednesday.

The pair was tried in absentia as they had been released earlier pending trial, the lawyer said.

"But after today's ruling, they will be pursued by security forces to apply the verdict," he said.

Abdullah and his friend were referred to court in May on charges of possessing and taking narcotics after they were arrested while sitting in a parked car in northeastern Cairo.

The authorities said that two hashish cigarettes had been found in their possession.

At the time, the family of the ousted president said the charges were fabricated in order to tarnish their reputation, but a subsequent drug test is said to have supported the charges.

Abdullah's brother, Osama, described Wednesday's ruling as "score-settling" by Egypt's army-backed authorities.

"The verdict merely aims to settle scores," Osama wrote on his Facebook page.

"We are no more important than the detainees and the martyrs," he added, referring to the hundreds of pro-Mursi demonstrators killed – and the thousands rounded up – since Mursi's ouster by the military one year ago.

Mursi – Egypt's first freely-elected president, who was ousted by the army last July after only one year in office – now faces trial on multiple charges, including incitement to murder, mass jailbreak and espionage.

The ousted leader says all the charges against him and his co-defendants are politically motivated. He has refused to recognize the trials' legitimacy and insists he remains Egypt's legitimate president.