US President Barack Obama has embarked on his first regional Middle East mission, seeking to build bridges between Washington and the Muslim world.The US leader is en route first to Saudi Arabia for talks with King Abdullah. On Thursday he will give a much-anticipated speech at Cairo University in Egypt, touching on the Middle East peace process but not unveiling a detailed plan. The US leader’s rhetoric and Muslim roots have kindled hope among Muslims – but many say they will judge Obama on actions, not words. Officials hope the visit will set a new tone in relations with the Muslim world ahead of the US troop withdrawal from Iraq and a tougher stance towards Israel over the Palestinians. It is also being seen as an attempt to counter the growing influence of extremism, particularly in Iran.