* Shell cuts 2016 capex by extra $2 bln, operating costs by $3 bln
* Savings will help keep dividend safe, Shell says
* Expects to complete deal by Feb. 15
* Major shareholder Aberdeen Asset Management says supports deal (Recasts to focus on break-even price, adds shareholder comment, further details, share prices)
By Ron Bousso and Karolin Schaps
LONDON, Dec 22 (Reuters) - Royal Dutch Shell's proposed $53 billion takeover of rival BG Group will work even if future oil prices are in the low $60s a barrel, it said on Tuesday in announcing another $5 billion cut in spending next year to weather low oil prices.
The company previously said the break-even oil price for the deal was $65 a barrel.
Publishing its prospectus for shareholders on Tuesday, Shell set Feb. 15 as the completion date for the deal, the largest in the energy sector in a decade and one that helped make 2015 a record-breaking year for mergers and acquisitions.
Shareholders of both companies will vote on the deal at meetings to be held on Jan. 27 and 28. Some major stakeholders have already voiced support for the transaction, although others have voiced concern that Shell might be overpaying in the light of the more than 35 percent drop in the oil price since the deal was announced in April.
Brent crude is currently trading near 11-year lows at around $36.50 a barrel and analysts polled by Reuters predict an average price of $57.95 in 2016.
"We're supportive of the deal from a strategic perspective. It makes a lot of sense to put the two companies together," Ben Ritchie, senior investment manager at Aberdeen Asset Management, a top ten investor in both Shell and BG, told Reuters.
Shell's A shares last traded in London up 3 percent at 1486 pence while BG's shares were up 3.3 percent at 923.6 pence.
Shell on Tuesday cut its capital spending plan for next year for the combined group by $2 billion to $33 billion and operating costs by another $3 billion, saying this would bolster its ability to weather the industry's downturn and maintain its dividend payments.
The company also said it would stop scrip dividend payments in 2017 and undertake a share buyback programme worth at least $25 billion between 2017-2020.
"We have moved decisively in 2015 on spending and portfolio, and I am determined we will act decisively again in the coming years," Chief Executive Ben van Beurden said in a statement.
Both companies will give a glimpse into their 2015 trading performance on Jan. 20, ahead of their respective shareholder meetings, and full-year results will follow in early February.
"We expect the combined entity to have one of the most resilient cash cycles in the sector," said Jason Gammel, oil industry analyst at Jefferies, who rates Shell's shares a 'buy'.
The takeover deal, which offered a 50 percent premium to BG's April 7 share price and was worth $70 billion then, includes a cash payment of 383 pence per BG share, which Shell plans to cover by increasing its debt.
BG confirmed in a separate statement that its chief executive Helge Lund, along with Chief Financial Officer Simon Lowth would both leave the company once the deal is concluded.
Lund, formerly chief executive of Norway's Statoil, only joined BG two months before the deal was announced.
BG said on Tuesday that Lund has now agreed with the company's non-executive directors to forego around a third of his remuneration package, or around 3.7 million pounds, if the deal is completed. (Additional reporting by Soumithri Mamidipudi in Bengaluru; editing by David Evans, Greg Mahlich)