This was CNBC's live blog covering European markets.

European stocks close slightly lower

Europe's Stoxx 600 index has provisionally ended Monday's session 0.08% lower — slightly off earlier lows, but reflecting a wait-and-see sentiment among investors who are still braced for any announcements out of U.S.-China trade talks taking place in the U.K. today.

It was a quiet day for data and earnings, but big market moves came from London listings. Chip designer Alphawave jumped 20% after agreeing to a $2.4 billion takeover by U.S. semiconductor giant Qualcomm, while technical instruments-maker Spectris soared 60% after confirming that it is in talks over a takeover by private equity group Advent International.

And in more news out of the U.K. capital, Nvidia CEO Jensen Huang pledged to boost investment in the country's artificial intelligence sector at London Tech Week, describing a "Goldilocks" opportunity.

On Tuesday, we'll be monitoring more from London Tech Week, as well as the European Defence and Security Summit in Brussels, the Paris Finance Forum and the Nvidia GTC AI conference, also in Paris. Data is due on U.K. jobs and wages. See you then.

— Jenni Reid

TikTok to open new London office, boost UK hiring

Chinese-owned video app TikTok on Monday announced it's opening a new office in London, doubling down on its investments in the U.K.

TikTok, which is owned by China's ByteDance, said it's developing a new 135,000 square foot office in London's Barbican district. It is slated to open in early 2026.

The space will complement TikTok's existing 88,500 sq ft head office in Farringdon, which the tech giant opened in 2022, and takes TikTok's overall U.K. infrastructure investment to £140 million ($189.5 million).

Alongside its announcement of a new office, TikTok also committed to add 500 new jobs in the U.K., which would take its overall headcount in the country to 3,000.

—  Ryan Browne

European stock markets slip

European stocks have retreated through Monday's session, with the regional Stoxx 600 index 0.28% lower at 1:58 p.m. in London and all major bourses in the red.

Global investors are awaiting updates from the U.S.-China trade talks, which begin in London Monday. U.S. National Economic Council Director Kevin Hassett told CNBC on Monday he expected it "to be a short meeting with a big, strong handshake," as Washington seeks confirmation China will restore the flows of critical minerals.

The euro and the British pound were both last trading around 0.1% higher against the U.S. dollar.

— Jenni Reid

THG shares hit an all-time low. Will it ever rebound?

Myprotein maker THG's share price tumbled to an all-time low on Monday, yet Jefferies says investors can double their money with the stock.

The cosmetics and dietary company's shares have lost nearly 96% of their value since the company went public on September 16, 2020, according to FactSet.

Top-line growth has gone into reverse for the company and has fallen by around 20% since reaching a high of 2.5 billion euros ($2.9 billion) for the year ending December 2021.

However, analysts at investment bank Jefferies suggest the company is battling macro-economic factors — such as the impacts of tariffs on its cosmetics division, as well as sustained "elevated" prices for whey, a key ingredient for its dietary business — and expects a rebound for the stock.

"With the current year set to absorb the near-term effects of whey, tariffs, and demerger-related one-offs, [financial year 2026] looks set to be the year in which THG demonstrates its underlying potential - we anticipate both Beauty and Nutrition will be in robust growth, and this should drop through to a year of strong cash generation - the template for future years," said Jefferies' Andrew Wade and Grace Gilberg, in a note to clients on May 8.

JPMorgan analysts, though, took the opposite view. They point to the company's first-quarter results, which missed their estimates by 7%, which was already below consensus. The analysts said the company's executives will need to demonstrate a turnaround before shares rally.

"While management maintained guidance for [financial year 2025] (for mid-single digit group revenue growth including a return to growth in Nutrition), we argue a weak start to the year has set a high bar for delivery through the remainder of the year at a time of heightened market uncertainty and growing risk to consumer demand," said the Wall Street bank's analysts led by Lara Simpson in a note to clients in late April.

— Ganesh Rao

Alphawave shares surge on Qualcomm takeover

Shares of London-listed chip designer Alphawave have surged more than 20% after the company agreed to a $2.4 billion takeover by U.S. semiconductor giant Qualcomm.

The California-headquartered firm will pay 183 British pence ($2.48) per Alphawave Share in an all-cash deal.

Qualcomm announced its intention to bid for Alphawave in early April, when Alphawave shares were valued at 94 pence, giving the final cash offer a 95% premium.

Analysts had previously expected the bid to complete as Alphwave has significant intellectual property rights in high-speed connectivity. The company boasts of multiple customers, including a hyperscaler that analysts believe is Amazon's AWS.

— Ganesh Rao

Advertising giant WPP's CEO to retire

WPP Group CEO Mark Read is set to retire at the end of the year after more than 30 years at the company, including seven years as chief executive, the firm said.

Shares of WPP have recorded a negative total return of 41% over Read's tenure, compared to the 49% achieved by the FTSE All-Share index and 54% returned by the FTSE 100 index.

WPP added that the search for a successor to Read was also under way.

"After seven years in the role, and with the foundations in place for WPP's continued success, I feel it is the right time to hand over the leadership of this amazing company," Read said in a statement to investors.

"I am excited to explore the next chapter in my life and can only thank all the brilliant people I have been lucky enough to work with over the last 30 years, and who have made possible the enormous progress we have achieved together."

Here are the opening calls

Good morning from London! This is CNBC's live blog covering all the action in European financial markets as the new trading week begins.

Futures data from IG suggests London's FTSE will open 7 points higher at 8,836, Germany's DAX up 3 points at 24,296, France's CAC 40 up 5 points at 7,801 and Italy's FTSE MIB 13 points higher at 40,595.

Global market focus will be on U.S.-China trade talks which are expected to take place in London on Monday. President Donald Trump announced Friday that Treasury Secretary Scott Bessent and two other Trump administration officials will meet with their Chinese counterparts in the capital as efforts to negotiate a trade deal continue.

In other news, CNBC will be at London Tech Week this week with Nvidia CEO Jensen Huang set to deliver a keynote speech on Monday morning. There are no other major earnings or data releases due.

— Holly Ellyatt

Global market action overnight

Asian markets climbed overnight as investors awaited trade talks between Washington and Beijing later on Monday, and digested China inflation and trade data.

Trade tensions are seemingly easing between the world's top two economies as China has reportedly granted temporary approvals for the export of rare earths, while jetliner Boeing Co has begun commercial jet deliveries to the Asian superpower.

U.S. equity futures were mostly flat overnight, with the S&P 500 trading near a record high and a busy week of potential market-moving news ahead.

U.S, inflation data is expected to be a key topic later in the week. The latest consumer price index is due out on Wednesday, followed by the producer price index on Friday. Traders will be looking for clues about how the current tariff rates are affecting the economy.

— Holly Ellyatt, Amala Balakrishner, Jesse Pound