Egypt's highest court on Sunday invalidated the Islamist-dominated Senate and a panel that drafted the constitution, throwing the country into fresh political uncertainty, as the presidency said the Senate will maintain its legislative powers until a new parliament is elected.

The Supreme Constitutional Court (SCC) said the law governing the elections of the Shura Council was unconstitutional, as were the rules for the selection of the members of a committee that drafted the constitution.

A draft law regulating Egyptian civil society groups has become a barometer of the Islamist government's commitment to the ideals of the democratic uprising that brought it to power, with the text raising concerns both at home and abroad.

President Mohammed Morsi, who referred the bill to the Islamist-dominated senate on Wednesday, pledged that he "does not aspire to control civil society," in a departure from his overthrown predecessor Hosni Mubarak's strongman tactics.

An Egyptian court on Saturday ordered the release of two policemen accused in the 2010 death of Khaled Said, who became a symbol of the fight against police torture, judicial sources said.

In the opening hearing of the retrial of Mahmud Salah Mahmud and Awad Ismail Suleiman, the Alexandria Criminal Court ordered both men freed because their preventative detention had expired.

Four Mexican tourists were killed on Friday in a fiery road accident in Egypt's Sinai Peninsula, South Sinai's governor told Agence France Presse, with police and medics putting the toll at six.

Seventeen tourists, all Mexican, were injured in the crash, governor Khaled Fouda told AFP, adding that two were in critical condition.

The sacking of Egypt's Opera House head has triggered a new political battle against President Mohamed Morsi, this time by artists who accuse the Islamist's Muslim Brotherhood of aiming to control cultural institutions.

The artists have taken to strikes, demonstrations and cancelling shows to counter what they say are Islamist designs on key cultural institutions.

Egypt's presidency said Tuesday it will submit a proposed law regulating civil society groups to the senate, insisting it reflects the values of the country's democratic uprising despite accusations it is restrictive.

The bill regulating foreign and local non-governmental groups would be submitted on Wednesday to the senate, which also acts as an interim parliament, Walid Zoghby, who helped to draw up the draft legislation, told Agence France Presse.

Europe's Digital Agenda commissioner Neelie Kroes on Monday welcomed a pledge by Egypt to maintain an 'open' Internet that would not be subject to government shut downs, as was the case during the 2011 uprising.

Kroes, Vice-President of the European Commission responsible for the Digital Agenda, met Monday with Egypt's Telecommunications Minister Atef Helmy during a visit to Cairo.

U.S. Secretary of State John Kerry on Saturday again pressed Egyptian President Mohammed Morsi to make concrete progress on economic reforms and rights, warning continued U.S. and global aid was at stake.

The Egyptians vowed that they had taken some steps, but Kerry "said we need to be able to show Congress that you've taken the necessary reforms," a senior State Department official said on the sidelines of an African Union summit.

Egyptian President Mohamed Morsi appealed Wednesday to the opposition for unity, in the face of criticism he is failing the revolution that brought him to power almost a year ago.

"To all those who love Egypt, to the opposition, those who love this country and care for its interests, let's proceed together... help each other, love each other more... and move forward," said Morsi.

 Kidnappers on Wednesday released three Egyptian policemen and four soldiers seized in the Sinai, the army said, leading to the reopening of a Gaza border crossing that police closed to protest the abductions.

"The seven security personnel have been released by their kidnappers in Sinai," military spokesman Ahmed Aly said in a statement carried by Egypt's official MENA news agency.