US president Donald Trump threatened on Monday to end a cease fire with Iran, dismissing Iran’s proposal to end the war as “a piece of garbage.”

• For more financial news, visit News24 Business. 

The US dollar extended gains for a second straight session on Tuesday, underpinned by sustained uncertainty over the ‌Middle East conflict that drove investors into the greenback as a traditional ⁠safe haven.

The greenback rose sharply in March as the currencies of oil-reliant economies such as Japan and the ⁠euro area were heavily sold after oil prices surged following Iran’s effective closure of the Strait of Hormuz. It weakened again after 7 April, the start of a ceasefire, which US president Donald Trump threatened on Monday to end, dismissing Iran’s proposal as “a piece of garbage.” The greenback now stands close to its pre-war levels.

“It appears ‌unlikely that a breakthrough would be achieved before the Trump-Xi summit later this week,” said Mohit Kumar, an economist at Jefferies.

Trump is expected to arrive in Beijing on Wednesday, where Iran is set to be among the topics discussed with Chinese President Xi Jinping.

“As long as crude oil prices stay high, because of the US’ blockade [of Iranian ports] and Iran’s threat to tanker traffic in the Gulf, the dollar will stay strong,” said Thierry Wizman, global forex and rates strategist at Macquarie.

“The toll that high oil prices will take on the rest of the world’s economies will be much more pernicious than the toll the US,” he added.

Oil ‌prices rose 2% on Tuesday ⁠as hopes for a deal to end the war on Iran faded.

Wizman also argued that the US administration has probably decided that its economic blockade of Iran - the ‘economic war’ - could be more effective than resuming bombing runs.

The US dollar index, a measure of its value against a basket of major foreign currencies, was up 0.35% at 98.30. It was at 97.85 on 27 February and hit 100.64 in late March. It fell below its pre-war levels late last week.

In late morning trading, the rand was weaker at R16.53/$, from below R16.45 late on Monday.

Investors are also closely watching the monetary outlook, with the Federal Reserve now expected to keep rates higher for longer to tackle inflationary pressures, while traders are betting that the European Central Bank will hike its depo rate to about 2.75% by year-end from the ⁠current 2%.

The euro fell 0.33% to $1.1744.

Eyes will be on a US inflation report due later in the session, which is forecast to show that consumer prices rose 0.6% last month after jumping 0.9% in March, according to a Reuters survey of economists. Estimates ranged from a 0.4% gain to a 0.9% rise.

The data could reinforce the view that the ⁠Federal Reserve is likely to keep interest rates unchanged in the near term. Traders have priced out the prospect of rate cuts for the year compared to the two cuts expected before the Iran war broke out.

The Japanese yen jumped suddenly in the late Asian session on Tuesday, stoking speculation of a “rate check”, often a precursor ⁠to currency intervention. The dollar was last at 157.57 against the yen, up 0.25% on the day, after US Treasury Secretary ‌Scott Bessent said he had ‌great confidence that Bank of Japan Governor Kazuo Ueda will guide the central bank to a “very successful” monetary policy. Japan’s authorities have supposedly spent nearly $63.7 billion (R1 trillion) in the current round of interventions.