UK energy supplier Centrica has warned that warm weather and weaker commodity prices in the first quarter had hurt its margins at its energy supply business.
But the company stopped short of revising any annual financial targets.
The firm also used a first-quarter trading statement ahead of its annual shareholder meeting to fire off another warning shot against any UK government moves to cap energy tariffs.
Theresa May's ruling Conservative Party has pledged to introduce a cap on energy prices in a bid to tap voter discontent about rising household bills.
"This will lead to reduced competition and choice, and potentially higher average prices," Centrica said, referring to the proposal.
Analysts said these political risks continued to weigh on Centrica's share price, which fell about 5% when the Conservative policy was unveiled two weeks ago.
Centrica said it had lost 261,000 customers since the start of the year, with most of those losses associated with a large block of customers switching suppliers, a spokeswoman said.
Britain's biggest utilities have been facing severe pressure from smaller suppliers entering the market and snapping up customers by offering cheaper tariffs.
Centrica said warmer weather that usual in Britain and North America had weighed on consumer energy demand in its two main markets, mainly hurting gross profit margins at its UK business.
Lower prices for oil and British gas and power since its last financial update in February also had negative impact, Centrica said, as they make its power plants less profitable and reduce returns from the sale of its North Sea oil and gas.
Nevertheless, the company maintained its main financial targets for the year, including reducing debt to £2.5 billion to £3 billion, a level at which its CEO said the company would consider raising its dividend.
Centrica cut its dividend two years ago and again last year as earnings were hit hard by weak energy prices.
