The Finance Department says it is considering issuing the long-term bond through a process of syndication in the near future, if market conditions are right.
It says given the current low yield environment issuing such bonds in the ultra-long sector would contribute to a reduction in future refinancing risk.
Currently the longest maturing federal bond is 30 years.
Bank of Montreal chief economist Doug Porter says there would be advantages for the government if it were able to borrow money for half a century at a cost not much higher than the 2.94 per cent currently on the 30-year bonds.
He says insurance companies and pension funds would be the natural customers for such long-term treasury bills.