This is CNBC's live blog covering European markets.

European markets edged higher on Monday as a shortened trading week began in the run-up to Christmas.

The pan-European Stoxx 600 index was up 0.4% during morning deals, with most sectors in positive territory.

Trading is expected to be relatively muted in the run-up to Christmas, with European markets set to be closed, or close early, for Christmas Eve and remain shut on Christmas Day.

Overnight, Asia-Pacific markets started the week on a positive note, with investors digesting a press conference relating to the merger of Japanese automakers Honda and Nissan.

The carmakers confirmed on Monday that they had begun merger talks. Shares of France's Renault, which owns a minority stake in Nissan, were around 0.7% lower at 9:08 a.m. London time.

Back in Europe, revised figures showed the U.K. economy flatlined in the third quarter of the year, with GDP growing 0% in the three months to September.

Aviva agrees deal to buy Direct Line in $4.7 billion deal

British insurer Aviva has reached an agreement to buy competitor Direct Line, the companies announced Monday.

The cash and share offer will compensate Direct Line shareholders with 0.2867 Aviva shares for each Direct Line share held, as well as 129.7 pence ($1.63) in cash and up to 5 pence in dividends.

The companies said the agreement valued Direct Line's entire diluted share capital at around £3.7 billion ($4.65 billion), based on Aviva stock's closing price on Nov. 27.

Aviva's London-listed shares were 0.3% higher at 10 a.m. London time, while shares of Direct Line gained 3%.

— Chloe Taylor

UK economy stalled in the third quarter

Britain's economy failed to achieve any growth in the three months to September, revised figures from the U.K.'s Office for National Statistics showed on Monday.

A preliminary estimate for the third quarter, published by the ONS last month, said U.K. GDP grew at 0.1% during the period. However, the final data released on Monday showed 0% GDP growth from the previous quarter.

Earlier this month, data from the ONS showed the U.K. economy had unexpectedly contracted in October.

— Chloe Taylor

Honda, Nissan schedule press conference amid merger reports

Vehicle making giants Honda, Nissan and Mitsubishi have scheduled a joint press conference for 8 a.m. London time on Monday, amid rumors that Honda and Nissan are set to begin merger negotiations.

Reports of a potential tie-up first emerged last week, boosting shares of French carmaker Renault, which owns a minority stake in Nissan. Mitsubishi is an existing partner of Renault and Nissan.

— Chloe Taylor

CNBC Pro: 'The next Nvidia': Broadcom is the AI chip stock to own in 2025, investor says

Broadcom is more likely to deliver big gains for investors in 2025 than AI chip leader Nvidia, according to fund manager Stephen Yiu.

Yiu, portfolio manager of the Blue Whale Growth Fund, said that while Big Tech giants, such as Microsoft, Amazon, Google and Meta Platforms, had bought up Nvidia's graphics processing units (GPUs) in vast quantities, they were now also developing their own custom chips for artificial intelligence applications in an effort to diversify.

CNBC Pro subscribers can read more here.

— Ganesh Rao

European markets: Here are the opening calls

European markets are expected to open higher Monday.

The U.K.'s FTSE 100 index is expected to open 8 points higher at 8,098, Germany's DAX up 12 points at 19,919, France's CAC up 7 points at 7,291 and Italy's FTSE MIB up 76 points at 34,031, according to data from IG.

Data releases include final U.K. and Spanish economic growth data.

— Holly Ellyatt