CNOOC Ltd has announced it will take drastic measures to get the money it needs to buy Nexen Inc in the wake of the Chinese oil giant's disappointing first-half profits.

CNOOC Chairman Wang Yilin said at a news conference in Hong Kong on Tuesday that the company will reduce its dividend almost by half to help raise the $15.1 billion it needs to buy the Canadian company. CNOOC will also raise the additional capital it needs.

CNOOC, China's top offshore oil producer, last month launched the country's biggest foreign takeover bid by agreeing to buy Nexen, whose global portfolio includes oil sands and shale gas. But CNOOC's first-half profits then fell nearly 20 percent.

"Our strong cash inflow should sufficiently support the planned Nexen acquisition. However, we still need to raise capital to fund our cash bid for Nexen to improve our capital structure that can foster the company's long-term development," Wang said.

The Nexen deal should help China gain both the technology and operating experience it needs to extract potentially huge domestic reserves of bitumen, heavy oil and shale oil, said industry experts. CNOOC has only nine years' worth of reserves based on its current production - one of the lowest among global oil majors.

"The acquisition should enable CNOOC to build up its oil and gas reserves by 20 to 30 percent. This is very important for CNOOC as its market valuation can be significantly raised because of the jump in reserves in future," said AMTD Securities Business Manager Kenny Tang.

As to whether CNOOC should divest some of Nexen's assets to lessen the US Congress' potential opposition to the acquisition, Wang stressed: "The acquisition is a pure commercial agreement, and we have no plans to divest any of Nexen's assets after the proposed acquisition."

CNOOC's share price fell nearly 3 percent to close at HK$15.10 ($1.95) in Hong Kong trading on Tuesday. Investors were disappointed with the sharp cut in its interim dividend, which was slashed to HK$0.15 per share from HK$0.25 a year ago.

CNOOC reported a net profit of 31.9 billion yuan ($5.02 billion) for the first half of this year - a 19 percent decline from 39.3 billion yuan a year ago due to weak sales and the resource taxes. The net profit figure is below the average forecast of 34.2 billion yuan polled by Reuters.

The company's oil and gas sales dropped slightly by 1.4 percent to 95.66 billion yuan in the first half. The special oil-gain levy in the same period amounted to 13.64 billion yuan, and that has taken a toll on the company's profit performance.

CNOOC produced 160.9 million barrels of oil equivalent in the first half, down 4.6 percent year-on-year, in the aftermath of a spill at its Penglai 19-3 field in eastern China's Bohai Bay last year. Oil production in the Penglai oilfields dropped 4 million barrels to 72 million barrels from a year earlier due to the shutdown of Penglai 19-3. The company said it was confident of meeting its production target of 330-340 million BOE set for this year, versus 331.8 million BOE in 2011.

The oil explorer's first-half, all-in costs hit $34.6 per barrel, up 13.1 percent from the average level in the whole of 2011, partially offsetting an 8.1-percent increase in realized crude oil prices and a 20-percent rise in realized natural-gas prices, CNOOC said.