(KUNA) -- Israel played down on Monday remarks made by Palestinian President Mahmoud Abbas indicating that the Palestinian National Authority was seeking to release two leading Palestinian activists held by Israel in exchange for an Israeli soldier held by Islamic activists in Gaza. "President Abbas' remarks are not serious," Israel Radio quoted an official source as saying, in reaction to remarks made by the Palestinian president, saying that authority was seeking to set free Marwan Al-Barghouti, a leading activist of the mainstream Palestinian organization Fatah, and Ahmad Saadat, Secretary General of the Marixt-oriented Popular Front for the Liberation of Palestine (PFLP), as part of "an operation to swap them for an Israeli soldier held in Gaza." Al-Barghouti has been sentenced to life in prison for involvement in "sabotage acts against Israel," while Saadat is held for complicity in assassination of an Israeli minister.Abbas, in remarks broadcast by an Egyptian television network on Sunday, said he believed that Palestinian prisoners should be freed, including Saadat and Al-Barghuoti "for the pair have been unjustly put behind bars." He indicated that the Egyptian Government was involved in contacts with the Palestinian Islamic group, Hamas, to try free the Israeli soldier.