The former Governor of the Papua New Guinea province of Bougainville, John Momis, says he feared further confrontation if he challenged the results of May's election of an autonomous government.
Mr Momis was one of the favourites to win the presidency in the elections in late May, but he got just half the votes of the victor, Joseph Kabui.
Mr Momis has claimed on several occasions that there was widespread electoral fraud, but last month he withdrew an electoral petition.
He says this was because of death threats he had received and fears that a challenge could spark clashes.
"I decided not to take it up because it would probably lead to further confrontation between my supporters and Kabui's supporters. So I said the best thing to do was to withdraw and let the new Government have its own way and be at liberty to place policies so the people can decide for themselves."
The international election monitoring team and UN officials declared the elections clean and fair.