Rob Altemeyer and Dave Gaudreau came up with the oath declaring that "leaking confidential information to the media is a betrayal of our party, our caucus and the causes we fight for."
"I have not been the source of any such leaked information nor will I be in the days to come," the oath reads.
It also promises to work toward reconciliation within the governing party. The pledge will hang in the caucus room for several weeks but no one should feel pressured to sign it, the backbenchers said.
"We're not on a witch hunt," Gaudreau said Tuesday. "We're not looking for anybody to do this. We're just saying it's time for people to come together and unite all of us."
Premier Greg Selinger barely managed to hold on to his job in a leadership contest prompted by internal dissent and the resignation of five top cabinet ministers who called on him to step aside.
Selinger declined interview requests on the pledge. His spokesman, Paul McKie, sent an emailed statement saying all cabinet ministers, MLAs and staff made a pledge when they took their oath of office or signed their employment contracts.
"If there are staff or MLAs who wish to sign the pledge they are welcome to do so, but certainly there is no requirement from the premier or caucus that they sign," he wrote.
When he was asked if Selinger plans to sign the pledge, McKie just resent a copy of the statement.
No one else was on hand to immediately sign the pledge and those in the legislature declined to comment on it. Christine Melnick, a former cabinet minister who was kicked out of caucus for criticizing Selinger, went into the caucus room but wouldn't say if she signed it.
Finance Minister Greg Dewar declined an interview but said through a spokesperson that he would be signing the pledge.
Altemeyer, who slammed those who challenged Selinger's leadership, said the pledge is not meant to further divide the party. Those who called on Selinger to step down are welcome to sign it, he said.
"If I haven't done anything wrong and if I believe in what a document says, I should feel pretty comfortable signing it," Altemeyer said.
Former finance minister Jennifer Howard, one of the cabinet rebels, declined to comment. Former attorney general Andrew Swan also declined comment but confirmed he will run again in the next election.