London pre-open: Stocks to fall as US-Iran tensions ramp up again

20th Apr 2026 07:29

(Sharecast News) - London stocks were set to slump at the open on Monday, while oil prices rose as tensions between the US and Iran ramped up again over the weekend and after the US intercepted an Iranian cargo ship trying to breach its maritime blockade.

The FTSE 100 was called to open down around 45 points. At 0720 BST, Brent crude was up 5.2% at $95.08 a barrel.

Ipek Ozkardeskaya, senior analyst at Swissquote, said: "Last week was marked by a questionable rally on hopes that peace was just around the corner, but weekend news dampened that optimism, and the week opens on a mixed note with many unanswered questions.

"The Strait of Hormuz is reportedly closed again, Iran is not happy with the US blockade and even less with a ship being seized a few hours ago, and is no longer willing to attend the upcoming negotiations until the blockade is lifted. Donald Trump continues to threaten to destroy the country's power plants and bridges.

"As a result, US crude jumped at the open but has since given back part of its earlier gains."

On home shores, industry data showed house prices ticked higher in April despite a spike in mortgage rates following the outbreak of war in the Middle East.

According to the latest house price index from Rightmove, prices rose 0.8%, taking the average asking price up to £373,971. This is despite the average two-year fixed mortgage rate now standing at 5.42%, compared to 4.25% before the US first attacked Iran at the end of February.

Stiff competition among sellers further supported prices, with the number of homes for sale at an 11-year high for the time of year.

In corporate news, engineering group Renishaw lifted earnings and revenue guidance for the second time in three months on the back of "particularly strong" demand from the semiconductor and electronics manufacturing equipment, and defence & aerospace sectors.

The company now expects annual revenue of £775m to £805m and adjusted profit before tax of £145m to £165m compared with upgraded guidance of £740m - £780m and £132m - £157m given in February.

"We are actively managing the challenges and increasing costs imposed by ongoing economic and geopolitical uncertainties and supply chain pressures," Renishaw said in a trading statement.

Fintech group Plus500 lifted its full-year profit outlook following a "strong" first-quarter performance.

The company now expects FY 2026 revenue and earnings before interest, tax, depreciation and amortisation to be ahead of current market expectations of $779.3m and $360.4m respectively.

Drugmaker GSK said that its relapsed/refractory multiple myeloma treatment Blenrep had received approval from China's National Medical Products Administration, making it the only anti-BCMA cleared for use in the country.

GSK said Blenrep's Chinese approval followed a priority review of its application and Breakthrough Therapy Designation for its combination with bortezomib and dexamethasone based on the potential to provide "substantial improvement" over available therapies.