Nafez Dabaki, one of the alleged suspects, said in the video that he had been offered 50,000 Jordanian dinars ($70,500) if he blew himself up at a mosque where Haniya was praying.
Dabaki said he was asked three times to carry out the attack.
Mohammed Kheil, another alleged assailant, said he had been asked to kill Haniya at a public rally.
Kheil said he carried 25kg of explosives in a backpack at the rally but left after being spotted by security guards.
Said Siyam, a senior Hamas official, said Hamas is increasingly less inclined to engage in dialogue with Abbas and his aides.
"How can we talk about dialogue with this group, after we discovered this conspiracy which received the blessing of senior leaders who are sitting in the Muqataa (Abbas' headquarters) in Ramallah," Siyam said.
He said Arab leaders have been urging Hamas and Abbas to co-operate.
"But at this stage, we cannot ignore this conspiracy and we cannot show any mercy for those who were involved in this conspiracy," Siyam said.
In response Abbas' office said that Hamas "lost its credibility when it cheated and spilled Palestinian blood, and violated all national and moral values".
In the past Hamas has asked Abbas to resume contacts between the two factions that were broken after it took control of Gaza from his Fatah faction.
Abbas, who runs the West Bank, has said he will only talk to Hamas if it steps aside in Gaza.