Iraq's interim Prime Minister Iyad Allawi declared martial law on Sunday and said a U.S.-led military offensive against the rebel-held city of Falluja could not be delayed much longer. Insurgents have stepped up attacks against U.S.-led forces and Iraqi police to show their muscle before the U.S. offensive on Falluja and police said gunmen killed 22 policemen in three attacks on Sunday. Allawi was doing all he could to find a peaceful solution, his spokesman Thair al-Naqib said. "He still hopes that it may be possible to avoid a major military confrontation in Falluja ... He is, however, not optimistic," Naqib said. The Americans say they are only awaiting the word from Allawi, who returned from Europe on Saturday, to attack. Allawi declared a 60-day state of emergency across Iraq, except the region of Kurdistan, to ensure security before elections scheduled for Jan. 27. "This will send a very powerful message that we are serious," Allawi told reporters. "We want to secure the country so elections can be done in a peaceful way and the Iraqi people can participate in the elections freely, without intimidation by terrorists and by forces who are trying to wreck the political process in Iraq." --More 0121 Local Time 2221 GMT