A massive demonstration is due to be held in Cairo as protesters step up their efforts to force President Hosni Mubarak from power. Organisers say they hope one million will come onto the streets in what is expected to be the biggest show yet. A rally is also planned in Alexandria. Egypt's powerful army has vowed it will not used force against the protesters. Meanwhile, new Vice President Omar Suleiman says he will hold cross-party talks on constitutional reform. Mr Mubarak reshuffled his cabinet on Monday to try to head off the protests, replacing the widely despised Interior Minister Habib al-Adly. But correspondents say that the army's statement has been a major blow for President Mubarak, and appears to have encouraged protesters. The BBC's Middle East editor Jeremy Bowen, in Cairo, says that the feeling that change is coming in Egypt is getting stronger. Too much has happened too quickly to go back to the way things were before, he says. At least 100 people have been killed across the country since protests began a week ago following an internet campaign and partly inspired by the ousting of President Zine al-Abidine Ben Ali in Tunisia last month. Egypt has since cut off internet in the country and text messaging services have been disrupted. Google announced late on Monday that it is operating a special service to allow people in Egypt to send Twitter messages by dialing a phone number and leaving a voicemail. 'Overwhelming atmosphere' Some protesters defied the curfew and continued to camp out in Tahrir Square through the night, saying they will stay there until Mr Mubarak's 30-year-long rule ends. One of them, Tarek Shalabi, told the BBC that groups were camped out in tents or sleeping out in the square, and described the atmosphere as "overwhelming". "We're here because we want to make a statement. We're not going until Mubarak steps down," he said. He said a stage had been set up where people could go up and make speeches, read out poetry or sing or chant political slogans. "It has a festive feel to it," he said. "We all have one thing in common. We all hate the current regime," he said. Another demonstrator, 45-year-old lawyer Ahmed Helmi, said: "The only thing we will accept from him is that he gets on a plane and leaves". On Monday, the Egyptian army said it respected the "legitimate rights of the people". In its statement, carried on Egyptian media, the military said: "To the great people of Egypt, your armed forces, acknowledging the legitimate rights of the people... have not and will not use force against the Egyptian people." Our correspondent says the announcement is absolutely critical because it takes away a huge measure of uncertainty from the mind of any potential demonstrator. Whatever happens next, this will change the Middle East, our correspondent adds. 'Legitimate' In his statement, Mr Suleiman said the president had ordered new government policy to be outlined "in the next few days". The review would include "clear and definite policies" to tackle unemployment, poverty, corruption and the cost of living, the statement said. There would also be new elections in some districts where there was evidence of irregularities in last November's parliamentary poll. Meanwhile, the US state department has despatched a special envoy to Cairo, former ambassador to Egypt Frank Wisner. Concerns have also grown about the economy, as global oil prices on Monday topped $100 (£62) a barrel amid fears of the ongoing unrest. Source: BBC