(Bloomberg) — Asian stocks retreated after Federal Reserve Chair Jerome Powell warned about economic risks and big-name investors fueled doubts about valuations. Treasuries added to gains.

Shares slipped from Sydney to Hong Kong, though declines were shallower than seen on Wall Street. Futures on the S&P 500 fluctuated after the index briefly fell Wednesday below 2,800 — a level that’s provided support in the past month. Powell said the threat of a lasting downturn could deepen without additional government spending. The Australian dollar fell after data showed a record plunge of over half a million jobs in April.

The rally in global equities from March lows is showing further signs of stalling this week amid suggestions from some investors that stocks had run up too far amid the economic uncertainty. Meantime, addressing bets on the adoption of a negative interest-rate policy, Powell said such a move was not being considered. Still, he stopped short of completely ruling the tool out as an option.

“Views are beginning to firm that the 2020 bear-market rally may have run its course,” said Matthew Sherwood, head of investment strategy for multi-asset at Perpetual Investment Management Ltd.

Powell also suggested that additional fiscal support could be needed. On that score, Republicans rejected a $3 trillion stimulus measure drafted by House Democrats, but the draft plan has the seeds for an eventual, smaller compromise.

Elsewhere, oil nudged higher as investors weighed stockpile declines against a darker outlook for demand and economic recovery. After the close of regular trading, Cisco Systems Inc. gave a sales forecast that beat Wall Street expectations, sending shares higher.

Here are some key events coming up:

• U.S. weekly jobless claims data is due Thursday.
• China on Friday releases industrial production and retail sales data for April.

These are some of the main moves in markets:

Stocks

• Futures on the S&P 500 dipped 0.1% as of 12:31 p.m. in Tokyo. The gauge decreased about 1.7% on Wednesday.
• Japan’s Topix index declined 0.6%.
• Hong Kong’s Hang Seng Index slid 1%.
• The Shanghai Composite fell 0.5%.
• South Korea’s Kospi index retreated 0.9%.
• Australia’s S&P/ASX 200 Index lost 0.9%.
• Euro Stoxx 50 futures fell 0.5%.

Currencies

• The yen was at 106.91 per dollar, up 0.1%.
• The offshore yuan held at 7.1082 per dollar.
• The euro bought $1.0812, little changed.
• The Aussie fell 0.3% to 64.36 U.S. cents.

Bonds

• The yield on 10-year Treasuries dipped one basis point to 0.64%.
• Australia’s 10-year yield fell six basis points to 0.90%.

Commodities

• West Texas Intermediate crude rose 0.7% to $25.47 a barrel.
• Gold was at $1,714.35 an ounce, little changed.