Canadian Natural Resources Ltd. says it's committing $2 billion of this year's capital budget to advancing its Horizon project and then expects the oilsands operation's funding requirements to drop in 2017 and thereafter.

The Calgary-based company views Horizon as a key part of its future business plan, as it depends less on conventional sources of oil and gas.

The full 2016 capital budget, including spending on Horizon Phases 2B and 3, has been set at between $3.5 billion and $3.9 billion.

CNRL says the Horizon expansion budget will drop to $1 billion in 2017 and to zero in 2018, after Phase 3 starts production in next year's fourth quarter.

The budget projection was contained in CNRL's latest financial report, which showed it eked out a small profit in the fourth quarter but ended 2015 with a full-year net loss of $637 million or 58 cents per share.

The three months ended Dec. 31 showed $131 million of net income or 12 cents per share, which was an improvement over the third quarter but down from nearly $1.2 billion or $1.09 per share in the fourth quarter of 2014.