In Japan, the BOJ began its two-day meeting. Analysts broadly expect the BOJ will introduce fresh stimulus measures, which could include pushing interest rates deeper into negative territory or expanding its asset-purchase program, which buys securities including Japanese government bonds and exchange-traded funds.
"If the BOJ decides to act this week, they could expand the quantitative and qualitative easing (QQE) program or decide to reinvest maturities. If nothing happens this week, we expect the BOJ will act definitively in September," Jennifer Vail, head of fixed income research at U.S. Bank Wealth Management, said in a note.
But she added that the bank expected coordinated fiscal and monetary stimulus in Japan.
On the fiscal front, on Wednesday, Japanese media agency Jiji reported that Prime Minister Shinzo Abe was preparing a stimulus package worth 28 trillion yen ($265.30 billion), which exceeded initial estimates of around 20 trillion yen.
Peter Boockvar, chief market analyst at The Lindsey Group, said in a note it was still unclear how much of the 28 trillion yen stimulus plan would be new and how much of it would be "repackaged to make it seem huge."
"The timing of this chatter was likely done purposely ahead of the BOJ meeting where [BOJ Governor] Kuroda can have an idea of how much more paper he gets to now buy," said Boockvar.
The yen strengthened to the 104 handle against the greenback Thursday morning, trading as high as 104.50 before retreating to 104.66 as of 2:50 p.m. HK/SIN, compared with levels near 107 in the previous week, as traders await the BOJ's decision due Friday.
In company news, shares of Samsung Electronics closed down 1.31 percent after the smartphone maker announced its second-quarter earnings before market open.
Samsung reported revenue of 50.94 trillion won for the quarter ended June 30, a 2.4 trillion won increase on-year, while operating profit for the same period was at 8.14 trillion won, a 1.24 trillion won uptick on-year.
The company said both its handset and component businesses performed strongly to lead earnings growth, with its IT and mobile communications division seeing an improvement, led by higher sales of the flagship Galaxy S7 and S7 edge smartphones.
Nintendo shares, meanwhile, closed down 5.49 percent at 21,080 yen, as traders reacted to its first-quarter operating losses of $47.33 million, which the Japanese gaming company announced on Wednesday after market close.
Shares of major Australian miner, BHP Billiton, closed up 0.55 percent at 19.97 Australian dollars, despite a Reuters report that said the miner will book a charge of up to $1.3 billion to cover the costs of a dam disaster at the Samarco iron ore mine in Brazil last November.
BHP Billiton may have tracked other Australian iron-ore producers higher after the metal's price rose overnight, although its gain lagged peers Fortescue and Rio Tinto, which tacked on 4.76 percent and 2.10 percent respectively.