Katsav's tenure as president seems to be ending in disgrace after he was forced to take leave of absence following sexual misdemeanour charges being levelled against him.
Authorities have since said they intend to indict him on suspicion he raped a former staff member and sexually assaulted three other women who worked for him.
Opposition
Peres was endorsed as his party's candidate for the post on Tuesday by Ehud Olmert, the prime minister.
Although he will be the favourite to win the parliamentary vote to decide the presidency, Reuven Rivlin, his rival for the job from the opposition Likud party, is set to write a letter to MPs warning against voting for 83-year-old Peres.
The Haaretz newspaper reported that Reuven will distribute a letter to members of the Knesset warning them against degrading the role of the president, a largely ceremonial role.
"A blatantly political selection will transform the presidency into just another political position, and turning the presidency into a prize for lifetime achievement, or political compensation for past disappointments, will undermine the restoration of the presidency's public standing," Reuven was reported as writing.