Nigeria's government wants the country's top judge to be suspended pending the outcome of his fiercely-disputed trial on corruption charges, a court was told on Tuesday.Chief Justice Walter Onnoghen went on trial last week at the Code of Conduct Tribunal where he is facing six charges relating to the non-declaration of foreign currency bank accounts.The case is politically charged as the government has been accused of trying to influence the judiciary by removing Onnoghen, who would rule on any election disputes. Africa's most populous nation goes to the polls to elect a new president and parliament on February 16. Concerns have already been expressed about attempts to rig the result.Prosecutor Aliyu Omar told the tribunal that Onnoghen had been formally served with a summons but he was not present for Tuesday's hearing."What we are asking for is for him to step aside and we have filed an application for that," he said. "We are not asking him to resign but we are asking him to step aside for the period of this trial."* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook. Onnoghen's lawyer, Wole Olanipekun, said the hearing should be adjourned until the outcome of separate applications to halt the proceedings.But the tribunal rejected the request, adjourning the case until January 28.Ahead of the election, there have been concerns that both the ruling All Progressives Congress and the main opposition Peoples Democratic Party are looking to buy votes.But the PDP has gone further, casting doubt on the impartiality of the electoral commission, alleging some of its staff have been compromised.Buhari embarked on a high-profile anti-corruption campaign after taking office in 2015, which the PDP has criticised as a political witch-hunt.His opponents say the main opposition has been unduly targeted by means of the security agencies and courts like the Code of Conduct Tribunal.Senate leader Bukola Saraki was brought before the tribunal on charges of false declaration of assets but was ultimately cleared by the Supreme Court.