Egyptian protesters were massing Friday for sweeping "departure day" demonstrations to force President Hosni Mubarak to quit after he said he would like to step down but fears chaos would result.
Thousands who had bunkered down for the night in Cairo's Tahrir Square, focal point of an unprecedented uprising against Mubarak now in its 11th day, were joined from early morning by protesters who began streaming in from across the city, correspondents said.
After the bloody clashes of recent days between the protesters and stone-throwing loyalists of the Mubarak regime, protest stewards and troops alike were wearing hard hats.
Both groups were carrying out identity checks at entrances to the square to prevent it being infiltrated by provocateurs.
Defense Minister Mohammed Hussein Tantawi himself visited the square with military top brass to assess the scene, state television said.
Vice President Omar Suleiman, the reported focus of US plans for a post-Mubarak future, had demanded late on Thursday that the protests come to an end but he also promised the army would "not use any violence."
Washington has been increasingly strident in its criticism of the violence against the protesters which has left a least eight people dead and more than 800 hurt in the past few days, saying it has evidence that it has been orchestrated.
State Department spokesman Philip Crowley said US officials had traced the violence to "elements close to the government and the ruling party" even if it is not clear how far "up the chain" it goes.
In an interview with US network ABC, Suleiman denied that pro-government elements had been responsible for deaths among the protesters, insisting: "They behaved very well."
Asked about shooting into the crowds, Suleiman replied, in English: "No. Nobody being killed by rifles or by snipers. No way."
The State Department spokesman said Washington was concerned the violence might be a dress rehearsal for Friday, the Muslim day of rest, which opposition leaders have designated as "departure day" for Mubarak.
The opposition has called for gigantic demonstrations across the nation after the midday prayers and were hoping for an even larger turnout than on Tuesday, when more than one million people poured onto streets.
But protesters trying to reach Tahrir Square to join Friday's rally complained that paratroopers in riot-gear who were manning a cordon in surrounding streets, were allowing access through just one checkpoint.
"We want another entrance, the people want to pray," one would-be protester shouted at the soldiers as noon prayers approached.
"They want to tire people out, they say we're the [Muslim] Brotherhood, but we're not the Brothers, we're the people," said protester Hathim, a 29-year-old engineer, referring to Egypt's most powerful opposition group.
In his first interview since the protests erupted, Mubarak pointed the finger at Islamist group, which has been outlawed in Egypt for half a century," ABC television's Christiane Amanpour reported.
The veteran leader was "fed up with being president and would like to leave office now, but cannot, he says, for fear that the country would sink into chaos," Amanpour said.
"He told me that he is troubled by the violence we have seen in Tahrir Square over the last few days but that his government is not responsible for it. Instead, he blamed the Muslim Brotherhood," she added.
The vice president made the same accusation, although he earlier told state television that he had invited Brotherhood representatives to join a dialogue with the regime on the political transition.
"We will look into [the violence], into the fact it was a conspiracy," Suleiman, adding that it could have been instigated by some "with foreign agendas, the Muslim Brotherhood, certain parties or businessmen."
European leaders meanwhile joined Washington in demanding an immediate start to the political transition.
"Vice President [Joe] Biden urged that credible, inclusive negotiations begin immediately in order for Egypt to transition to a democratic government that addresses the aspirations of the Egyptian people," a White House statement said.
EU foreign policy chief Catherine Ashton said a start to dialogue between Egypt's authorities and the opposition is "absolutely essential."
The Egyptian opposition has refused to enter negotiations with the regime until Mubarak steps down, rejecting as totally inadequate his pledge to step down when his current term of office -- his fifth -- ends in September.
Amr Salah, a representative of those organizing the Tahrir Square demonstrations, told AFP they "will not accept any dialogue with the regime until our principal demand is met, and that is for President Hosni Mubarak to step down."
And the National Association for Change rejected any talks with the regime before Mubarak goes, spokesman Mohammed Abul Ghar told AFP.
The association includes former UN atomic energy watchdog chief and Nobel peace laureate Mohamed ElBaradei, Muslim Brotherhood members, the Kefaya [Enough] movement and other political parties.
But Arab League chief Amr Mussa, a one-time foreign minister to Mubarak, said he doubted his former boss would leave any time soon.
"I do not think he [Mubarak] will leave. I think he will stay until the end of August," Mussa told France's Europe 1 radio.
Egypt's regional rival Iran meanwhile waded into the crisis with supreme leader Ayatollah Ali Khamenei telling the faithful in a sermon that the protests in Egypt, which have sent shock waves around the Arab world, were a vindication of the message of the 1979 revolution in Tehran.
Khamenei said there was an "Islamic awakening because of the Islamic revolution of the great Iranian nation and it is showing itself today."