An appellate court on Tuesday upheld the sentence of two and a half years prison for a former health and welfare minister in connection with a corruption scandal involving ousted President Park Geun-hye.

The Seoul High Court delivered the sentence to the 61-year-old Moon Hyung-pyo, who is accused of pressuring the National Pension Service to approve a controversial merger of two Samsung units deemed vital for a smooth leadership transfer to the group's heir Lee Jae-yong.

The court also retained the lower court's two and a half year sentence on Hong Wan-sun, then-head of the NPS asset management division, on charges of dereliction of duty. He is accused of inflicting losses on the pension fund by ordering the merger's approval.

The higher court acknowledged the prosecution's argument that Moon was well aware that the presidential office Cheong Wa Dae had a keen interest in the Samsung merger, as a former presidential secretary testified.

Moon has claimed that he knew nothing about Cheong Wa Dae getting its fingers into the deal and that the argument had been accepted by the lower court.

"Notwithstanding the alleged pressure from Cheong Wa Dae, it does not acquit the defendant of the liabilities in which he forced NPS staff into duties that they had no obligation to do," the court said.

Moon, who headed the ministry from 2013-2015, was indicted in January on charges of abuse of power and lying under oath when he denied the charge against him during a parliamentary hearing in November.

Samsung's Lee has also been on trial for bribing Park and her close confidante to the tune of tens of billions of won, seeking government influence to move the merger forward in 2015. (Yonhap)