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* Benchmark closes at 6,300 level for first time since Jan2008
* BHP U.S. shale asset sale lifts index
* AMP flags financial impact from Royal Commission inquiry(Updates to close)
By Nikhil Nainan
July 27 (Reuters) - Australian shares closed the week attheir highest level since early 2008, with Friday's tradingbuoyed by news that BHP, the world's biggest miner, had agreedto sell its U.S. shale assets and promised to return allproceeds to its shareholders.
BHP provided a strong lift for the S&P/ASX 200 index, which closed 0.9 percent higher at 6,300.2, enough toscore a second straight week of gains.
Nearly a year after putting its U.S. shale assets up forsale and after months of market anticipation, BHP agreed to sellits shale oil and gas assets for $10.8 billion, with BP Plcpicking up most of them.
The better than expected sale price and the resultingexpectations of an enticing future share buy-back provided afillip to shares, which rose over 2 percent to their to theirhighest in more than two months.
"I think it (the deal) has certainly increased thelikelihood of a buy-back and buy-backs have certainly beensomething that's been driving markets globally," said DamienRooney, director of equity sales at Argonaut.
In contrast to BHP's fortunes, shares of AMP slidover 5 percent to their lowest in nearly 15 years after the firmwarned costs stemming from an inquiry into financial sectormisconduct would eat into first-half profits.
The wealth manager had flagged A$530 million ($391.46million)of costs it would to use to compensate customers forpoor advice, among other things, while saying underlying netprofit for the first-half would fall to between A$490 millionand A$500 million, lower than a year prior.
The Royal Commission has exposed systemic wrongdoing at AMP,wiping A$5.5 billion from its market value since it began inFebruary, with Friday's trading update providing an earlyfinancial impact from the inquiry.
Nonetheless, financials held up as the top constituents onthe benchmark led gainers.
The 'Big Four' banks gained within a range of 0.7 percent to1.6 percent, with Australia and New Zealand Bankingoccupying the top spot among the banks.
New Zealand's benchmark S&P/NZX 50 index climbed 0.7percent, or 63.68 points to finish at 8,996.16.
Auckland Airport and Fisher & Paykel HealthcareCorporation Ltd boosted the index, rising 2.4 percentand 1.4 percent, respectively.($1 = 1.3539 Australian dollars)(Reporting by Nikhil Kurian Nainan in BengaluruEditing by Shri Navaratnam)
