Latest violence comes day after reports revealed more than 10,000 soldiers have deserted the Syrian army, with as many as half the conscripts not reporting in the last three call-ups.
Scores killed in Tuesday's clashes, including 14 troops ambushed by opposition.
The radical Islamist Al-Nour party that won 25 to 30 percent of the vote in first two rounds of elections says they would not object to having contact with Israel.
Salafi Al-Nour party says will welcome talks with Israel; new Israeli envoy in Cairo says will try to open communication channels with Islamist groups.
Clashes raging since Friday in and around Tahrir, aepicenter of popular uprising that toppled longtime leader Hosni Mubarak in February; government crackdown unprecedented.
Plan calls for withdrawing the Syrian army from towns, freeing thousands of political prisoners, starting dialogue with the opposition and letting monitors into the country.
Senior Fatah official says Palestinian President Abbas will chair Cairo meeting on Thursday.
Unofficial results put Muslim Brotherhood ahead with 39 percent of the vote, Salafi Al Nour with 31 percent; liberal Wafd party wins 22 percent.
Cameras catch soldiers beating protesters to death; 10 people killed in weekend of violence.
Senior diplomatic official tells Haaretz, ambassador must talk to 'anyone who wants to and agrees to talk to him, even if those contacts are not made public.'