(Bloomberg) — Gold climbed after a run of three weekly gains, as heightened uncertainty over US trade policy unsettled markets and hurt the dollar.

Bullion rose as much as 1.4% toward $5,180 an ounce. President Donald Trump said Saturday he would impose a global tariff of 15% to preserve measures after the Supreme Court ruled against his use of emergency powers to set duties. The weaker dollar made the metal cheaper for many buyers.

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The court ruling has cast doubt over deals the US has negotiated with major trading partners. The European Parliament’s trade chief said he’ll propose delaying ratification of an agreement with Washington until there’s more clarity, Indian officials will postpone a trip to the US, while a member of Japan’s ruling party called the situation “a real mess.”

Gold’s recent run of gains has helped the metal to recover ground following a sudden rout at the turn of the month, which had dragged prices down from a record. The advance has been underpinned as many of the long-term factors aiding the commodity — including heightened geopolitical tensions and investor wariness of sovereign bonds and currencies — remain intact.

“There are enough structural factors in favor of gold in the medium term,” said Vasu Menon, strategist at Oversea-Chinese Banking Corp. “In the short term, however, expect gold prices to be volatile after the sharp gains in recent months given still-unfolding developments with US trade policy, and the situation in Iran.”

What Bloomberg Strategists Say…

Gold’s strength amid a lower positioning from hedge funds shows that there’s further position upside. The Commodity Futures Trading Commission data shows that the net-long position for gold futures have fallen to the lowest level in nearly a year.

Mark Cranfield, Markets Live strategist

In the Middle East, traders are watching a standoff between Washington and Tehran. While the two nations are in talks over a potential deal over Iran’s nuclear program, the US has amassed a vast military force in the region, prompting concern that there could be limited strikes or a full-blown conflict.

Gold rose 1.3% to $5,174.75 an ounce at 11:02 a.m. in Singapore. The Bloomberg Dollar Spot Index dropped 0.2% after declining by the same amount on Friday. Silver climbed 3.4% to $87.53. Platinum and palladium also advanced.