Major European markets were mixed on Thursday, following the signing of a digital agreement between the United States and Iran that contributed to a decline in oil prices, while investors awaited hawkish signals from the US Federal Reserve.

The London Stock Exchange underperformed compared to other markets as a round of by-elections began, which could pave the way for the return of former Manchester mayor Andy Burnham to parliament if he wins the Mackersfield seat, potentially putting him in a position to challenge Prime Minister Keir Starmer for the party leadership.

Attention is also turning to the Bank of England, which is expected to announce its decision on interest rates later today.

The pan-European STOXX 600 index fell 0.4% to 636.75 points, Britain's FTSE 100 index declined 0.8% to 10,417.22 points, Germany's DAX index was flat at 24,927.58 points, while France's CAC 40 index rose by about 0.1% to 8,446.24 points.

UniCredit shares rose slightly by 0.3%, following reports of contacts with Delphin regarding a potential share swap deal involving the Del Vecchio family group's 10% stake in Generali in exchange for shares in the bank.

The newspaper Il Sole 24 Ore reported that this deal could raise UniCredit's stake in the insurance company to around 20%, while making Delphine one of the bank's major shareholders, led by Andrea Urcel.

In contrast, Saipem shares fell 2.2%, leading the losses, after notifying the European Commission of its merger with Subesia 7, a move that will be assessed for its impact on competition, particularly in the deep-sea systems market.

Brussels has also opened an investigation into the possibility that the deal received support from countries outside the European Union, according to media reports.

In the automotive sector, Stellantis shares fell by 1.2% after statements by CEO Antonio Velosa confirming that there is no intention to sell the Cassino and Maserati factories, with a move towards industrial partnerships with 51% ownership for the company and 49% for the partners.

US markets

In the US markets, the indices closed lower, with the Dow Jones down 1%, the Nasdaq down 1.3%, and the S&P 500 down 1.2%.

In Asia, Japan’s Nikkei index rose 2%, while Hang Seng fell 2% and Shanghai Composite declined 0.2%.

In the currency markets, the euro fell to $1.1513 from $1.1593 in yesterday's session, while the British pound recorded $1.3301 compared to $1.3396.