Egypt's top prosecutor Nabil Ahmed Sadek has declared the site where a Russian airliner carrying 224 passengers and crew crashed on Saturday to be off-limits, as a probe into the cause of the deadly crash continues.

The Airbus A321, operated by Russian airline Kogalymavia, crashed in Egypt's Sinai Peninsula on Saturday after losing radar contact almost half an hour after take off, killing all aboard, including 25 children.

The flight departed from the Sinai Red Sea resort of Sharm El-Sheikh en route to St Petersburg, Russia.

Sadek ordered on Saturday that the site of the plane wreckage in the Hassana area, some 70 kilometers (44 miles) south of the North Sinai city of El-Arish, be off-limits as investigations take place, a statement from the prosecutor's office said.

The decision bans removing any parts from the plane debris in the mountainous area without a prosecution permit and not until inspection work by the prosecutors and assigned technical committees is completed.

Egypt's Civil Aviation Minister Mohamed Hossam Kamal said that experts have begun analysing the black boxes of the plane, which contain the flight data.

At least 163 bodies have been recovered from the plane wreckage and sent to different hospitals, including Cairo’s Zeinhom morgue, Sunday's cabinet statement read.

The search for remains resumed at the site of the crash early Sunday morning as a Russian team of experts were helping to recover bodies and begin investigations into the cause of the crash, the statement added.

Both Cairo and Moscow dismissed allegations by the Siani-based Islamists militant group Ansar Beit Al-Maqdis it downed the plane.

In an interview with Russian state channel NTV, the wife of co-pilot Sergei Trukachev said her husband was complaining of the aircraft's condition.

Ayman El-Mokadem, an Egyptian official from the government's Aviation Incidents Committee, said that the pilot was experiencing technical problems and wanted to land at the nearest airport.

However, Civil Aviation Minister Hossam Kamel said that there is no record of any such request being made by the pilot.

"No problems with airliner"

Germany's Lufthansa, Dubai-based Emirates, and Air France all said they would stop flights over Sinai until the reason behind the crash is known.

United Arab Emirates airlines Emirates, Air Arabia and flydubai said they were re-routing flights to avoid flying over Sinai as a "security precaution".

Russian Transport Minister Maxim Sokolov and Russian Emergencies Minister Vladimir Puchkov arrived in Cairo late Saturday along with a team of experts to assist in the investigation by Egyptian authorities.

Minister Sokolov dismissed the claim by the ISIS group affiliate as inaccurate.

The quality of the fuel used by the Russian airliner met all necessary requirements, Russian Volga region transport prosecutors said on Sunday

The crew of the airliner also underwent medical tests recently and no problems were detected, Interfax news agency reported, citing prosecutors.

"The crew underwent a medical examination before flying to Sharm el-Sheikh, and they were declared fit to fly," said Maiya Ivanova from the Volga region transport prosecutors' office.