Asia stocks were mostly down on Monday in morning session, following a decline in US equities last Friday amid increasing worries American tax reform.
In Australia, the ASX 200 declined 0.25% by mid-day. The heavily-weighted financial subindex was down 0.5%, while the energy sector rose 0.6%.
Japan's Nikkei 225 fell 0.61%, while the Topix index fell 0.41%. In South Korea, the Kospi gave up early morning gains to trade down 0.29%.
Chinese markets traded lower, with the Shanghai composite down 1.12% while the Shenzhen composite fell 1.55%. In Hong Kong, the Hang Seng index traded fractionally lower at 29,171.
Energy prices were in focus amid reports of heightened tension in the Middle East between Saudi Arabia and Iran, following the resignation of the Lebanese Prime Minister Saad al-Hariri and the escalation of the Yemeni conflict.
The Organisation of the Petroleum Exporting Countries is also set to meet in Vienna on 30 November, where member states will decide if they would support an output cut deal beyond March next year.
Energy plays were mostly higher. In Australia, shares of Santos rose 1.9%, Woodside Petroleum was up 0.6% and Beach Energy was up 1.17%. Oil Search shares fell 0.56%.
In Japan, Inpex rose 0.4% and Japan Petroleum was up 0.58%.
In corporate news, Toshiba said it would raise 600 billion yen ($5.3 billion) from a sale of new shares, according to Reports. Toshiba shares were down 4.45% in late morning trade.
In the US, analysts were cautiously optimistic about the US tax reform getting done this year. Treasury Secretary Steven Mnuchin told CNBC's "Squawk Box" on Friday that he expects a Republican tax reform bill to be sent to President Donald Trump by Christmas.
In currency news, the US dollar traded at 93.961 against a basket of currencies at 10:00 a.m. HK/SIN, hovering near the 94.00 level it saw in the previous week. The Japanese yen traded at 112.02 to the dollar, while the Australian dollar fetched $0.7557.