Asia markets poised for mixed open amid spike in Treasury yields, Iran tensions

Asia-Pacific markets were poised to open mixed Wednesday as investors weighed elevated bond yields and renewed geopolitical tensions after U.S. President Donald Trump said he was "an hour away" from deciding whether to attack Iran on Tuesday before he was convinced to postpone the strike for a few days.

Yields on U.S. Treasurys advanced as investors continued to dump bonds on fears inflation is reigniting. The longer-dated 30-year Treasury bond yield was last trading almost 1 basis point lower at 5.174%. It briefly hit 5.197% during the session, marking its highest level since July 2007.

Japan's Nikkei 225 was poised to climb, with the Chicago futures contract at 60,835 and the Osaka counterpart last trading at 60,570 compared with the index's previous close of 60,550.59.

However, Hong Kong's Hang Seng index futures were at 25,603, lower than the index's last close of 25,797.85.

In Australia, futures last traded at 8,600, slightly lower than the S&P/ASX 200's last close of 8,604.7.

U.S. stock futures ticked slightly higher. S&P 500 futures added 0.14%, while Nasdaq 100 futures added 0.25%. Futures tied to the Dow Jones Industrial Average rose 55 points, or 0.11%.

Overnight on Wall Street, stocks closed lower with the S&P 500 posting its third straight losing session, as a jump in bond yields threatened the bull market.

The S&P 500 closed down 0.67%, ending at 7,353.61, while the Nasdaq Composite finished 0.84% lower at 25,870.71. The Dow Jones Industrial Average shed 322.24 points, or 0.65%, to close at 49,363.88.

— CNBC's Sean Conlon, Sarah Min and Lisa Kailai Han contributed to this report