Hong Kong (AFP) - Oil prices sank Thursday after Donald Trump suggested the latest US attacks against Iran would likely be short-lived.

The move helped most equities higher and eased pressure on bond yields, providing much-needed relief to markets, while the yen jumped more than two percent to extend a rally Wednesday that had fuelled fresh intervention talk.

Trading floors have been jolted since US strikes on Islamic republic targets in the Strait of Hormuz sparked tit-for-tat exchanges between the two and sent crude rallying as much as 10 percent.

The flare-up, which broke weeks of relative calm around the waterway – a crucial transit for a fifth of global oil and gas – fanned fears of another step up in already elevated inflation and put pressure on central banks to hike interest rates.

It also came just days after a hawkish speech by Federal Reserve boss Kevin Warsh that was seen by investors as a pivot towards a possible tightening of monetary policy.

Sentiment was given a much-needed boost Wednesday after the US president said the latest round of strikes could be over soon.

Asked how long the bombing campaign could last, he told reporters: “I don’t think too long.”

Meanwhile, CNN cited US officials as saying the military escorted 40 commercial ships loaded with 18 million barrels of crude through the strait, a wartime high.

The two main contracts Brent and West Texas Intermediate pared their gains Wednesday and on Thursday snapped their recent rally to drop more than one percent.

Yields on 10-year US Treasuries and Japanese government bonds of the same length both dipped.

The latest developments helped all three main US indexes higher, and while most of Asia followed suit in the morning traders turned a little more cautious in the afternoon.

Seoul, Sydney, Singapore, Manila, Mumbai, Bangkok and Jakarta all rose but Tokyo, Hong Kong, Taipei struggled. Shanghai was flat.

London and Frankfurt were flat but Paris slipped.

Weak US economic data also provided support. August private jobs creation coming in below expectations – and down from the previous month – along with job openings also missing forecasts, eased pressure on the Fed to hike borrowing costs.

Focus is now on the release Friday of the closely watched non-farm payrolls figures and next week’s consumer price index, which could play an outsized role in the Fed’s decision-making ahead of its September 16 rate decision.

The soft readings “finally offered a little relief… (and) gave the bond market a reason to stop climbing the stairs for a moment”, wrote Stephen Innes at Quintex Intel.

“Treasury yields eased, and stocks could finally breathe,” he added.

“The market is not suddenly celebrating weaker growth. It is simply rediscovering that slightly bad news may be exactly what it needs right now, especially if the alternative is a Fed that feels compelled to keep tightening into an oil shock.”

Still, he said that Trump’s comments have “taken some heat out of the worst-case inflation fears, but the geopolitical pot is still simmering”.

Investors are keeping tabs on Tokyo after a spike in the Japanese yen stoked speculation of more intervention by authorities.

The currency strengthened to 156.36 per dollar Thursday from just short of 160 Wedneday, when it had also seen a sharp advance.

Observers said it looked like officials had again stepped in as the yen had been giving back the gains seen in the wake of a historic Japan-US joint intervention at the end of July.

The gains also came after a top Bank of Japan board member suggested officials could hike rates more than the expected 25 basis points at their next meeting this month, and even announce another at the next gathering.

- Key figures at around 0810 GMT -

Tokyo - Nikkei 225: DOWN 0.2 percent at 64,214.48 (close)

Hong Kong - Hang Seng Index: DOWN 0.4 percent at 25,213.31 (close)

Shanghai - Composite: FLAT at 3,942.09 (close)

London - FTSE 100: FLAT at 10,759.11

West Texas Intermediate: DOWN 0.7 percent at $90.35 per barrel

Brent North Sea Crude: DOWN 0.8 percent at $94.88 per barrel

Dollar/yen: DOWN at 156.79 yen from 158.89 yen on Wednesday

Euro/dollar: UP at $1.1606 from $1.1584

Pound/dollar: UP at $1.3495 from $1.3484

Euro/pound: UP at 86.00 pence from 85.91 pence

New York - Dow: UP 0.6 percent at 53,061.95 (close)