"The State of Israel is executing a man today on the basis of impressions, without real time testimony, without evidence," Katsav told reporters as he left his home to make his way to prison. "One day, consciences will prick and you will see that you buried a man alive."

These are the words of former Israeli president Moshe Katsav as he arrived at Maasiyahu prison near Tel Aviv on Tuesday to being a seven-year jail term for rape.

Katsav, 66, was convicted of raping a former aide in December last year, but remained free while appealing the decision.

His sentence was upheld by the Israeli Supreme Court in November.

"Moshe Katsav will go to jail as planned and will receive the same conditions as other prisoners," Israel's minister for internal security, Yitzhak Aharonovich, told Israel Radio.

The former president has reportedly been placed on suicide watch and his lawyers have said they are concerned about his state of mind, according to The Jerusalem Post.

He is the first former Israeli head of state to be jailed.

Katsav resigned from the largely ceremonial post of Israeli president in 2007 amid allegations that he had raped a former presidential aide and sexually harassed two other female employees while in office.