As befits a company that was briefly the world's largest by market capitalisation, PetroChina has a nicely-developed sense of bathos. Just a month ago Asia's biggest crude producer was trumpeting its desire to “seize historic opportunities”. On Sunday the $330bn company agreed to pay $1bn for 45.5 per cent of a Singaporean downstream energy company.

Even assuming a mandatory offer for the remainder of Singapore Petroleum Company proceeds smoothly (not a given: shares on Monday closed below the offer price), this is small beer. PetroChina is light on leverage and the $2.2bn total price tag would barely dent its $13bn cash-pile. PetroChina spent more than that on its own refining and marketing operations last year, in spite of the fact the unit attracted less than 9 per cent of group capital expenditure. Nor is this a deal to send shivers down the spines of politicians and protectionists, as did CNOOC's bold but abortive bid for Unocal of the US four years ago. China has since tempered its ambitions, and this deal is more about dipping a toe into a regional hub than about securing resources. Nonetheless, the acquisition potentially gives PetroChina a more palatable offshore platform for international expansion.

At the margin, it gives a tad more exposure to downstream, which can be helpful when crude prices are subdued. Sinopec, the refinery arm of China's oil and gas triumvirate, has seen its share price rise 34 per cent year-to-date, comfortably outpacing PetroChina. And the offer price is carefully calibrated. At a 24 per cent premium to Friday's close, before the deal was announced, and 53 per cent to the undisturbed price, PetroChina can escape accusations of opportunism. The price represents 17-18 times this year's estimated earnings, in line with a couple of the bigger integrated players and a chunky premium to some Asian ones. Not game changing, but a tasty enough hors d'oeuvre.