Christian Wulff, the conservative state premier of Lower Saxony, was nominated today as the government's candidate for the next German president, according to dpa. Chancellor Angela Merkel's centre-right coalition proposed the 50-year-old as the successor to Horst Koehler, who unexpectedly resigned at the start of the week. In accepting the nomination, Wulff said that the office of president was "a great duty, with great responsibility. I look forward to the challenge. I think one can bring people together, do something for solidarity in our society, bring optimism in difficult times." The role of president is largely ceremonial, but can act as a form of moral compass for the nation. The next president is due to be formally voted into office by a special assembly on June 30. Merkel's coalition majority means their chosen candidate is likely to succeed. Merkel praised Wulff, saying he was a person with a strong sense of value who had an interest in people. "I am especially pleased that he is ready to take over responsibility for our country, in these times in which we find ourselves, in a major world financial crisis, at a time when the future of Europe is at stake," Merkel added. Opposition parties, the Social Democrats (SPD) and the Greens have proposed Joachim Gauck, a former East German dissident and the first federal commissioner of the Stasi secret police archives, as their candidate. A further candidate is yet to be named, from the former-Communist Left party. Earlier in the week, rumours had abounded that Labour Minister Ursula von der Leyen could become Germany's first female president. Wulff has built up a reputation as a shrewd regional politician with a low-key political style, who at times has opposed some policies of Merkel's government Becoming president would essentially put him above the political fray, just weeks after another of Merkel's CDU critics, Hesse state premier Roland Koch, announced his resignation. The post of president is elected by a special body known as a Federal Council, which comprises the entire membership of the Bundestag parliament, plus an equal number of representatives nominated by the 16 states.