The FTSE 100 closed slightly lower on Monday, below new best levels, and despite gains by gold miners as the yellow metal hit a new high.

The FTSE 100 index closed down 12.11 points, 0.1%, at 9,479.14. The blue-chip index had earlier hit a new all-time best level of 9,516.83.

The FTSE 250 ended down 97.88 points, 0.4%, at 22,099.74, and the AIM All-Share declined 0.89 of a point, 0.1%, at 795.63.

In European equities on Monday, the CAC 40 in Paris closed down 1.4%, while the DAX 40 in Frankfurt ended unchanged.

The CAC 40 tumbled after prime minister Sebastien Lecornu resigned.

President Emmanuel Macron appointed Mr Lecornu, a former defence minister, to the post last month, the third prime minister appointed since snap parliamentary elections in the summer of 024.

But the largely unchanged cabinet Mr Macron unveiled late on Sunday to work with Mr Lecornu sparked fierce criticism across the political spectrum.

Mr Lecornu’s allies in the centre-right Les Republicains indicated they could withdraw from his government because of the number of ministers planned to be included from Mr Macron’s Renaissance party.

“Lecornu was already expected to face a difficult confidence vote later this week but President Macron’s cabinet appointments, which were largely similar to the past government sealed Lecornu’s fate,” said Marc Chandler, chief market strategist at Bannockburn Capital Markets.

Barclays said Mr Lecornu’s resignation now leaves President Macron with two main options: appointing a new prime minister or dissolving the National Assembly.

Financial services took the brunt of the falls, with Societe Generale down 4.2%, BNP Paribas down 3.2%, AXA down 2.3% and Credit Agricole down 3.4%.

But losses were widespread. Car maker Renault fell 1.6%, Gucci owner Kering dipped 1.8% and retailer Carrefour declined 1.7%.

The yield on French 10-year bonds rose six basis points to 3.57%, while the euro traded lower.

The euro stood at 1.1706 dollars at the time of the London equity market close on Monday, compared with 1.1741 dollars on Friday.

Kathleen Brooks, research director at XTB said once again, France is “rudderless” politically speaking, which is also weighing on the stock market.

“While the political situation may not directly impact these companies, the fact that France’s largest and most prestigious companies are getting sold off today is a sign that investors are offloading French assets on a broad basis, and the risk is that this causes contagion elsewhere,” Ms Brooks said.

The pound was quoted slightly higher at 1.3471 dollars compared with 1.3469 dollars on Friday. Against the yen, the dollar was trading at 150.07 yen, higher compared with 147.43 yen.

Stocks in New York were mixed at the time of the London close. The Dow Jones Industrial Average was down 0.1%, the S&P 500 index was 0.3% higher and the Nasdaq Composite 0.5% to the good.

The yield on the US 10-year Treasury was quoted at 4.16%, stretched from 4.11% on Friday. The yield on the US 30-year Treasury stood at 4.76%, widened from 4.70%.

Advanced Micro Devices soared 27% after it announced a deal with OpenAi which could see the ChatGPT maker take a 10% stake over time.

Under the agreement, San Francisco-based OpenAi has agreed to purchase graphics processing units from AMD with a total power consumption of six gigawatts.

The first 1GW deployment of AMD Instinct MI450 GPUs is set to begin in the second half of 2026.

As part of the agreement, AMD has issued OpenAI a warrant for up to 160 million shares of AMD common stock, roughly 10% of the firm, structured to vest as specific milestones are achieved.

On London’s FTSE 100, Mondi plunged 16% as it revealed profitability dwindled in the third quarter of this year thanks mainly to softer volumes and weaker prices.

The Weybridge-based packaging firm saw its underlying earnings before interest, taxes, depreciation and amortisation drop 19% to 223 million euros for the third quarter of 2025 from 274 million euros in the second quarter, but was flat compared with the third quarter last year.

Jefferies said this was 11% below its “already cut” forecast of 250 million euros and implies 10% reductions to 2025 Ebitda forecasts.

“The profit warning was worse than we had expected,” analysts at Jefferies wrote.

A fresh surge in the gold price boosted Fresnillo, up 1.2%, and Endeavour Mining, up 2.8%.

Gold traded at 3,957.68 dollars an ounce on Monday, breaching 3,900 dollars an ounce mark for the first time, and up against 3,885.67 dollars on Friday.

The yellow metal was lifted by safe-haven demand as investors braced for a protracted US government shutdown.

Brent oil traded at 65.43 dollars a barrel on Monday, up from 64.61 dollars late on Friday, supporting BP, which rose 2.1%.

On the FTSE 250, Aston Martin hit reverse, down 10%, as it reported a lower full-year outlook for 2025, hurt by US tariff uncertainty and weakened demand.

The Warwickshire-based luxury car maker now expects total wholesale volumes for the full year to decline by mid-high single-digit percentage from 6,030 in 2024.

In addition, Aston Martin expects adjusted earnings before interest and tax “to be below the lower end of the range of market consensus … driven by the weaker volumes and pressure on the gross margin per vehicle”, the minimum estimate currently being a £110 million loss, “and no longer expects positive free cash flow generation in (the second half)”.

“Reduced 2025 expectations may clear the decks for a better 2026, but this remains a show-me story for investors,” analysts at Citi said.

The biggest risers on the FTSE 100 were Prudential, up 28.5p at 1,039.0p, Endeavour Mining, up 86.0 pence at 3,198.0p, BP, up 9.05p at 432.8p, Admiral, up 62.0p at 3,330.0p and Glencore, up 6.0p at 353.7p.

The biggest fallers on the FTSE 100 were Mondi, down 167.4p at 879.6p, Kingfisher, down 6.0p at 301.7p, BAE Systems, down 39.0p at 2,016.0p, Diageo, down 33.5p at 1,760.0p, and IMI, down 40.0p at 2,310.0p.

Tuesday’s global economic calendar has the Halifax house price index in the UK and trade figures in Canada.

Tuesday’s UK corporate calendar has full year results from veterinary services provider CVS Group, and half year numbers from fishing tackle and equipment retailer Angling Direct.

Contributed by Alliance News.