The pan-European STOXX 600 index dipped 0.1pc in thin trade with most of the Europe's country indexes in the red.

Sentiment remained shaky after three weeks of solid gains that have reclaimed almost all of a May sell-off, which generated European shares' worst monthly performance in more than two years.

Already subdued in anticipation of headlines from Sino-US trade talks expected over the weekend, sentiment took a further hit after US President Donald Trump signed an executive order imposing sanctions on Iran's Supreme Leader and other top officials.

London's FTSE rose slightly as energy and material stocks countered losses in most other sectors on the back of rising copper and oil prices.

Losses on the broader index stemmed mainly from the retail, auto and banking sectors.

Renault shares slipped 2pc. Nissan Motor smashed hopes for a quick fix to strained relations with Renault, saying inequality between the partners could unravel their two-decade-old automaking alliance.

Shares of France's Carrefour retreated a day after it became the latest Western retailer to retreat from the Chinese market. Rating agency Fitch downgraded the stock to 'BBB' from 'BBB+' after the announcement.

The banking sector fell ahead of a handful of speeches by US Federal Reserve policy makers, including Chair Jerome Powell.

The Fed is facing pressure from Trump to cut rates sharply in the face of a slowing economy, and markets now believe firmly that the panel will do so in July.

Any indication to the contrary would be likely to drive up short-term bond yields while also weakening stock markets, whose rally this month has been driven by expectations of more stimulus from both the Fed and the European Central Bank.

M&A CHEER

The technology sector was up 0.4pc on the back of Capgemini's purchase of smaller rival Altran for 3.6 billion euros.

"We think the deal makes strategic sense, helping Capgemini to capitalize on the digital transformation of industrial companies," analysts at Credit Suisse wrote in a note.

Capgemini rose 8.4pc to post its best day in 6-1/2 years, while Altran surged 21.2pc to reflect the selling price and posted its biggest intraday gain in 16 years.

Germany's trade sensitive DAX index slipped 0.4pc.

A US official said on Monday that Trump was "comfortable with any outcome" from the talks with Chinese President Xi Jinping when they meet at a G20 summit this weekend, cooling hopes for a substantive breakthrough.

"The US ... communicated that the market shouldn't put up their hopes too high for the coming G20 meeting," said Teeuwe Mevissen, a senior market economist at Rabobank.

"The maximum that can be achieved is a temporary truce like they did last time where they also decided to stop at least raising tariffs further."