British utility Centrica announced on Thursday it was selling a 40 percent stake in its Canadian natural gas business to joint venture partner Qatar Petroleum International for around $200 million.

The group, which owns the UK's largest energy supplier British Gas, also said it would not increase residential prices this year and warned its 2014 earnings would drop.

"While earnings are anticipated to fall in 2014, we expect an improvement in 2015, assuming more normal weather conditions and reflecting the prospects for underlying growth," said chief executive Sam Laidlaw.

Centrica said it expected full-year residential energy supply margins of around 4 percent this year, lower than its long-term target.