Asia's biggest oil and gas producer swung to a 27.7 billion yuan ($4.28 billion) first-quarter net profit, having posted a loss in the same period last year, and announced that it is setting up a new investment vehicle with a focus on strategic assets and low-carbon projects.

The new firm, CNPC Kunlun Capital Company, is 51% owned by PetroChina parent China National Petroleum Corp, 29% by PetroChina and 20% by CNPC Capital, with registered capital of 10 billion yuan.

PetroChina's first-quarter revenue was up 8.4% at 551.9 billon yuan, it said in a filing to the Hong Kong Stock Exchange.

Oil and gas output grew 0.8% to 417.1 million barrels of oil equivalent, with crude oil production down 4.9% while gas output was up 8% at 1.17 trillion cubic feet.

Refinery throughput rose 7.8% to about 3.31 million barrels per day, reversing close to a 10% drop a year earlier.

Its domestic gas sales rallied nearly 15% and refined fuel surged 20.9% as Chinese fuel demand rebounded in tandem with robust economic growth.

($1 = 6.4665 Chinese yuan renminbi)

(Reporting by Chen Aizhu in Singapore and Muyu Xu in Beijing; Eediting by David Goodman)