Suh's appointment does not require parliamentary consent, but any intense parliamentary opposition could pose a political hurdle to the new spy chief in charge of the country's key intelligence affairs.

The parliament's intelligence committee is expected to adopt the report on the results of the hearing on Tuesday.

Suh has been dogged by a set of allegations, including suspiciously high payments for his advisory role from a satellite TV company and a private institute.

The nominee received a monthly payment of 10 million won ($8,930) from KT Skylife for nine months from April 2012. He also obtained 120 million won while working as a non-standing advisor for Samsung Economic Research Institute for two years from July 2008.

Suh claimed that the payments were given in due consideration of his experience and the advice he provided to them.

The main opposition Liberty Korea Party has also taken issue with Suh's remarks in a media interview last year. Suh purportedly claimed that to address Pyongyang's nuclear conundrum, security assurance to the North's Kim Jong-un regime must be provided first.

Chung Woo-taik, the LKP floor leader, has called the remarks "dangerous and inappropriate."

How to reform the NIS is also at issue.

In a written statement Suh submitted to parliament Sunday, the nominee remained skeptical about Moon's pledge to remove the NIS division in charge of domestic intelligence to prevent the NIS from being embroiled in local politics.

Suh, however, said that it is difficult to make a clear distinction between domestic and overseas security intelligence given threats, including those from cyberspace, can come from both within and without.

Suh, 63, played a key role in preparing for the landmark inter-Korean summits held in June 2000 and October 2007. Moon's nomination of him was thus seen as his resolve to improve cross-border ties.

Suh joined the spy agency in 1980 and served as a deputy NIS director from 2006-2008. (Yonhap)