The Egyptian prosecution has ordered that charges of incitement of violence facing leader of the Freedom and Justice Party Saad El-Katatni be dropped.
The charges relate to clashes at the presidential palace in December 2012. El-Katatni will not be released from imprisonment as he is facing a number of other charges, including incitement of violence during clashes between Morsi's supporters and opponents in front of the Muslim Brotherhood's Cairo headquarters in June.
The prosecution also ordered the detention of the Brotherhood's second-in-command, Khairat El-Shater, for 15 days pending investigation on charges of inciting violence during the December clashes. El-Shater had already been detained without charge since his arrest on 4 July.
El-Shater will be further investigated on charges of inciting the forced detention and torture of anti-Morsi protesters as well as taking part in acts of “thuggery” and “terrorising citizens" during December's clashes, which took place between supporters and opponents of now-deposed president Mohamed Morsi in front of the presidential palace, leaving ten dead and dozens injured.
El-Katatni and El-Shater, along with a number of other Brotherhood figures, were arrested the day after Mohamed Morsi was ousted from power.
US Senators John McCain and Lindsay Graham - who visited Cairo Tuesday to take part in mediation efforts between Egypt's rival political camps - called for the release of Brotherhood figures from prisons.
A group of foreign envoys, including assistant secretary of state William Burns, the assistance to the EU envoy Bernadino Leon, and the foreign ministers of Qatar and the United Arab Emirates Khalid Al-Attiyah and Abdullah bin Zayed, reportedly visited El-Shater in prison on Sunday.
Egypt has been in a state of heightened tension as the Brotherhood insists on the reinstatement of Morsi while the government - which has renewed its intention to disperse the five week pro-Morsi sit-in - has called on Morsi's supporters to "give up violence" and reintegrate in the political process and the interim roadmap.