Rescuers recovered seven more bodies from the Nile after a party boat collided with a cargo ship earlier this week, raising the death toll to 36, Egyptian officials said Sunday.

The accident, the deadliest such incident on the Nile in years, occurred late Wednesday when the victims were celebrating an engagement on a vessel that was struck by a cargo ship.

Syria's President Bashar Assad acknowledged the shrinking ranks of his government's army in a rare public speech on Sunday, but insisted the force was still capable of beating rebel fighters.

Speaking in Damascus, Assad also said any "dialogue that is not based on the fight against terrorism would be meaningless".

The White House on Sunday backed Turkey's right to strike back at Kurdish militants, after waves of air and artillery strikes put a fragile ceasefire in jeopardy.

"Turkey has a right to take action related to terrorist targets," said deputy national security advisor Ben Rhodes after strikes against the outlawed Kurdistan Workers Party (PKK).

Rebel rocket fire on a government-held area of Syria's second city Aleppo killed five children, four of them brothers, a monitoring group said on Sunday.

The Saturday evening rocket struck the Shahba al-Jadida district in the west of the city, where loyalist forces have held out since rebels seized the east in 2012, the Syrian Observatory for Human Rights.

An Australian nurse was charged with terrorism offences for allegedly supporting the Islamic State group in Syria on Sunday after he voluntarily returned home from the troubled country.

The 39-year-old Melbourne father of five, named in local media as Islamic convert Adam Brookman, briefly faced a Melbourne court on Sunday after surrendering himself to officials in Turkey on Tuesday, Australian Federal Police said.

Kurdish militia have expanded their control over portions of a major Syrian city in their fightback against the Islamic State group, to the detriment of government forces there, a monitor said Saturday. 

"The Kurdish People's Protection Units (YPG) are advancing in Hasakeh city against IS and at the expense of the regime," said Rami Abdel Rahman, head of the Syrian Observatory for Human Rights. 

President Bashar Assad granted an amnesty on Saturday for people in war-torn Syrian who have dodged service or defected from the army, state news agency SANA reported.

According to SANA, Assad issued a decree "which grants a general amnesty to those who defected and are still in or have fled Syria".

An Australian nurse who allegedly worked alongside Islamic State militants has been arrested after voluntarily returning from Syria, police said Saturday.

The Melbourne-based father-of-five, widely named as Islamic convert Adam Brookman, surrendered to Turkish officials earlier this week ahead of his arrival in Sydney late Friday.

Three people were injured Friday when clashes erupted between far-right demonstrators and pro-refugee protesters in the eastern German city of Dresden, where hundreds of asylum seekers are due to be given shelter.

Some 200 members of the far-right NPD had gathered in protest against the arrival this weekend of 800 refugees, the majority from Syria, German news agency DPA reported.

Turkey's military Saturday carried out a new wave of air and artillery strikes against both Islamic State (IS) jihadists in Syria and Kurdish militants in northern Iraq, putting in jeopardy a fragile ceasefire with Turkish Kurds.

The two-pronged operation against IS and the outlawed Kurdistan Workers Party (PKK) -- two groups who are themselves bitterly opposed -- came after a week of deadly violence in Turkey the authorities blamed on both organisations.