British Prime Minister David Cameron visited Nigeria on Tuesday, pushing a message of trade, aid and democracy before making an early return home to deal with the spiralling phone hacking crisis. Cameron has come under increasing pressure over the scandal, and media tycoon Rupert Murdoch\'s appearance before a British parliamentary committee Tuesday looked set to overshadow his visit to Africa\'s largest oil producer. After talks with President Jacob Zuma in South Africa on Monday, Cameron flew into Lagos at the head of a business delegation to call on Africans to use trade, aid and political reform to make the most of \"Africa\'s moment\". But he was due to return home on Tuesday afternoon, several hours earlier than planned, to deal with the phone hacking crisis which has widened since he left London on Sunday afternoon with the resignations of two top policemen. Murdoch, son James and former top aide Rebekah Brooks on Tuesday faced a dramatic showdown with British lawmakers over the scandal. Despite the turmoil dominating the headlines at home, Cameron continued his schedule as planned Tuesday morning, first by visiting a clinic where he met women bringing their babies to be vaccinated against yellow fever. He later gave a speech to Lagos Business School at the Pan African University, ahead of talks with President Goodluck Jonathan. Addressing academics and business leaders, Cameron defended Britain\'s decision to spend 0.7 percent of gross national income on aid from 2013, and in its efforts to help those suffering from the drought in the Horn of Africa. At a time of major budget cuts at home, the aid budget is controversial. But he said aid should be used in a \"catalytic way\" to boost infrastructure and reduce trade barriers, saying that this, increased trade and a shift towards greater democracy on the continent could help transform Africa. \"It is now possible to imagine an Africa no longer dependent on aid, and a real source of growth for the whole world,\" Cameron and Jonathan said in a joint opinion piece published in Nigeria\'s Guardian newspaper. \"And the road to get there lies through freeing up the wealth-creating power of enterprise and trade.\" On a continent where China has made huge strides as a trade partner, Cameron admitted in his speech that British businesses needed to \"catch up\" to avoid missing \"one of the greatest economic opportunities on the planet\". Cameron highlighted the progress of democracy in Africa, praising Jonathan on his victory in recent elections, viewed as the fairest in nearly two decades in Africa\'s most populous nation despite major flaws. But he said that it was now \"time for the whole of Africa to meet the aspirations of people\", and also urged Africans to take responsibility for holding their leaders to account. \"These are the demands the people have made in Egypt, Tunisia and Libya. These are the demands that have propelled the Arab Spring,\" he said. \"And these are the demands, which supported by a revolution in trade and enterprise mean Africa can seize its own moment of opportunity.\" He couldn\'t escape the scandal at home however, with one person in the audience asking him a question about the News of the World and media independence. In his response, Cameron stressed the need for strong, independent news media, but also responsible regulation. Security was especially tight during Cameron\'s visit, with Nigeria\'s north having seen almost daily bomb attacks and shootings in recent weeks blamed on an Islamist sect. Lagos, the economic capital of some 15 million people located in Nigeria\'s southwest, has not been hit by such attacks. Cameron will arrive back in Britain late Tuesday to prepare for a statement to the House of Commons on the phone hacking crisis, and to answer questions about his own role in the affair. He is under increasing pressure over his decision to hire Andy Coulson, a former editor at the scandal-hit News of the World, as his media chief until January. Coulson was arrested earlier this month over alleged hacking and police corruption, although he denies any wrongdoing.