* Westpac up after CEO steps down due to money-laundering scandal
* Caltex Australia surges 13% on $5.84 bln takeover offer
* Bank of Queensland drops 9% to near 7-year low
By Niyati Shetty
Nov 26 (Reuters) - Australian shares clocked broad gains on Monday as Sino-U.S. trade deal optimism boosted market sentiment, while Westpac Banking Corp snapped four sessions of declines after the scandal-hit lender's chief executive resigned.
The S&P/ASX 200 index .AXJO rose 0.8%, or 52.50 points, to 6,783.90 by 1243 GMT, after adding 0.3% on Monday.
Westpac WBC.AX said its chief executive will step down and its chairman will bring forward his retirement as a money-laundering scandal rocked the country's second-largest retail bank. The leadership changes sent its shares up as much as 2.1%. will be up for more fines and issues but at the end of the day it will pass just like many of the other issues from the Royal Commission," said Brad Smoling, managing director at Smoling Stockbroking, referring to a public inquiry that found widespread misconduct in the financial sector.
Westpac shares slumped 8% over the previous four trading days since the financial regulator announced its lawsuit, wiping A$7.5 billion off the bank's market value.
The financial sub-index advanced with No. 1 lender Commonwealth Bank of Australia CBA.AX and National Australia Bank Ltd NAB.AX gaining 0.5% and 0.7%, respectively.
Bank of Queensland Ltd BOQ.AX , however, fell 9.1% to a near seven-year low and was the worst performer on the benchmark ASX index, after announcing a A$250 million discounted placement on Monday. Wall Street stocks hit new highs overnight on renewed hopes that the United States and China would reach a "phase one" trade pact to end their bruising tariff war before the end of the year. .N
Rising oil prices lifted the energy sub-index .AXEJ 2.3%, with heavyweights Woodside Petroleum Ltd WPL.AX and Oil Search Ltd OSH.AX rising 1.5% and 1.4%, respectively.
Caltex Australia CTX.AX surged 12.7% to a 15-month high, after announcing a A$8.61 billion ($5.84 billion) revised indicative takeover offer from Canadian convenience store operator Alimentation Couche-Tard Inc ATDb.TO . Group Ltd BHP.AX was marginally higher, a day after the world's biggest miner said it would pay $21.9 million to become the top shareholder in Ecuador-focused SolGold Plc SOLG.L . Tinto Ltd RIO.AX rose 0.7%, while Fortescue Metals Group Ltd FMG.AX added as much as 2.2% to its highest since July 2008, as demand concerns fuelled a rise in iron ore prices. IRONORE/
Export-oriented healthcare stocks .AXHJ gained 1.3% to a record high, with local shares of U.S.-based Resmed Inc RMD.AX advancing 1.7% and drugmaker CSL Ltd CSL.AX rising 1.6%.
Across the Tasman Sea, New Zealand's benchmark S&P/NZX 50 index .NZ50 added 0.6%, or 62.24 points, to 11,015.91.
Fuel distributor Z Energy Ltd ZEL.NZ and utilities firm Meridian Energy Ltd MEL.NZ were among the top performers on the index, rising 3.1% and 2.9%, respectively.
($1 = 1.4736 Australian dollars)