The new measures, which include dropping compulsory testing on entry, are due to be announced by the federal government later on Tuesday. Canada will also drop testing requirements for fully vaccinated Canadians who make short trips - less than 72 hours - abroad, the source said.
The global travel advisory for Canadians is also being changed. Previously the government recommended against all non-essential travel, and now it is only urging citizens to take precautions.
Several provinces, including Alberta, Saskatchewan, Quebec and on Monday Ontario, Canada's most populous province, have announced a relaxation of restrictions imposed during the pandemic as coronavirus infection rates fall.
Ontario said it will speed up its plan to remove proof-of-vaccination requirements and lift pandemic-related capacity limits for many businesses, while the western province of Alberta ended its mask requirements for school children on Monday.
Protesters have blocked border crossings and paralysed the centre of Ottawa for weeks asking for governments to roll back pandemic restrictions. Provincial premiers have denied loosening restrictions to appease them, saying instead that the limits are no longer needed to contain COVID-19.