Best Buy, the world's largest electronics retailer, has sent a shockwave through the troubled European market with its plans to bring its stores to the Continent.

The yellow ticket logo of the US group will take on brands such as Germany's MediaMarkt, the UK's Currys and Comet and France's Fnac. The US retailer, which had $40bn in revenues last year, is planning to roll into town at a time when the incumbents are struggling with depressed margins, a growing competitive threat from supermarkets and online rivals and worries over consumer spending.

By announcing the tie-up with Carphone Warehouse yesterday, the US group has also stolen the thunder of John Browett, the new chief executive of DSG International, who is to due to set out his strategy for Europe's second largest electronics group next week.

Mr Browett, who joined from Tesco at the end of last year, is familiar with Best Buy, having visited US executives at the chain during a marathon global tour of electrical retailing during his six months' enforced gardening leave from his former supermarket employer.

"He's got minimum one year, and probably two years, to get DSG's house in order," says David Jeary, analyst at Investec. That is the time it is expected to take Best Buy to get its European operation fully up and running.

The US group's £1.1bn ($2.15bn) purchase of a 50 per cent share in a retailing joint venture with Carphone will be immediately earnings accretive. It opens up an avenue of growth for a company that has 923 stores across the US as well as smaller operations in Canada and China. It also has plans to open in Mexico and Turkey.

Over the next three months, Carphone will start to stock laptops at its 2,400 stores following its successful entry into the PC market last year. In August, subject to shareholders' approval, the new venture will inherit the network that will continue to operate under Carphone's portfolio of brands.

But plans for the rollout of Best Buy's trademark "big box" format with stores trading under its own name were being closely guarded by Brad Anderson, chief executive of the US retailer, and Charles Dunstone, his counterpart at Carphone.

The UK will be the launchpad next year, although both men dodged questions as to how many Best Buy stores the venture would open. Mr Anderson did acknowledge there was an "incentive to develop a meaningful business in Europe as rapidly as we possibly can".

But the veteran retailer was keener to talk about the less tangible aspects of selling consumer electronics - which lie at the heart of the deal. "I think that fundamentally our industry is not doing a terribly good job for the consumer," said Mr Anderson.

After consumer research in the US and the UK, he was struck by the "tech stress" affecting shoppers on both sides of the Atlantic as they struggle to work out which of the increasingly complicated electronic products to buy and then how to make them work together. "Except for the accent we couldn't tell the difference between the people we were talking to in Minnesota and the people we were talking to in London." said Mr Anderson.

"Consumers in Europe are really ready for someone to come and try to do a better job," said Mr Dunstone, who has brought Best Buy's successful Geek Squad, its roaming technical service specialists, to the UK.

Bad service is a problem that Mr Browett at DSG will have to wrestle with: criticism of standards at his Currys and PC World stores is widespread.

Kesa, which operates Comet in the UK and Darty in France, will also have to deal with a newcomer that prides itself on its standards of service.

"Neither to any great extent cover themselves in glory on the customer service front," says Mr Jeary of Investec. "If those guys [Best Buy] can bring the scale of their global pricing power, plus pre-, during and post-sales service, it could be an interesting threat."

There could be an opportunity too. Some analysts said the company could decide the best route to bulking up quickly in Europe was via an acquisition of part or all of either Kesa and DSG.