The majority owner in the White Rose oil field says its started oil production from the South White Rose project in the Jeanne d'Arc Basin off Newfoundland's Grand Banks.
Husky Energy said the first well has been brought online about 350 kilometres southeast of St. John's.
A second well is expected to begin production in late summer, at which time net peak production from the South White Rose extension is expected to ramp up to about 15,000 barrels per day.
"South White Rose is Husky's second major subsea satellite tieback following the successful North Amethyst subsea project," said CEO Asim Ghosh in a statement Monday.
Husky Energy said it anticipates production from South White Rose and the North Amethyst field will offset "the impact of natural declines in the region."
Production on the Hibernia-level formation well beneath the North Amethyst field is expected to begin late this year, with peak production projected at 5,000 barrels per day.
Work at South White Rose began two years ago and was expected to cost more than $1 billion.