British Prime Minister Tony Blair called Sunday for a new UN resolution expanding sanctions against Sudan and said a no-fly zone over Darfur should be considered, as the European Union stepped up condemnation of "intolerable" violence in the region. "We need to get a new resolution in the United Nations which extends the sanctions regime," he told reporters after a European Union summit. "We need to consider, in my view, a no-fly zone," he said. "The actions of the Sudanese government are completely unacceptable." The United Nations currently has no sanctions against Sudan, but the EU has issued an arms embargo on Sudan and visa bans on a number of Sudanese officials. Blair said EU leaders had spent a "significant" part of their 50th anniversary talks discussing the "intolerable" Darfur situation. Efforts to impose tougher, UN sanctions on Sudan have made little progress in the face of Chinese objections. Military experts have also expressed doubt about the feasibility of imposing a no-fly zone over such a vast and remote area in central Africa. Blair was joined by German Chancellor Angela Merkel, whose country holds the rotating EU presidency, in raising the possibility of tougher sanctions. Calling the suffering of the people of Sudan "unbearable," Merkel said the UN should consider extending sanctions if Sudan fails to uphold UN resolutions aimed at stemming fighting. The two leaders spoke a day after Sudanese troops barred the UN humanitarian chief from visiting a refugee camp in the Darfur region whose residents have been raped and attacked by gunmen suspected of belonging to pro-government militias. "Even today, our thoughts are with the people in ... Darfur. The suffering there is unbearable," Merkel said at a celebration of the European Union's 50th birthday in Berlin. "We call on the Sudanese President (Omar) al-Bashir to finally accept the terms of the UN Resolution, and I say openly: we must consider stronger sanctions," said Merkel. The suffering of 4 million people in Sudan's Darfur region _ caught in fighting between rebels, the government and the pro-government militias _ has been taken up by celebrities and Nobel laureates, including Bob Geldof, Guenter Grass, Harold Pinter and Vaclav Havel, who urged the EU to take more decisive action in the region. In an open letter to Merkel on Sunday, US film star George Clooney added his voice, calling on EU president Germany to take "decisive action" in the region in the face of al-Bashir's failure to respond to the UN resolutions. "The coming together of Europe's leaders this weekend is an ideal opportunity for the most stringent of sanctions to be put in place," Clooney wrote. "This genocide is happening on our watch. And what we do to stop it will be our legacy." More than 200,000 people have been killed and more than 2 million displaced in four years of fighting in Sudan, and the pro-government janjaweed militias are accused of widespread atrocities against ethnic civilians. Blair met with Ishag Mekki, from a London-based group representing survivors of the violence. Mekki welcomed the EU's support, but said "we do not statements, we need action." On Saturday, UN Secretary General Ban Ki-moon failed to persuade Egypt to push Sudan's leader to accept a UN peacekeeping mission in the region.