Despite the challenge from players like Amazon, 68 percent of retailers say stores remain the most important channel for shoppers and one in three plan to expand their footprint, according to a survey by the Australian Centre of Retail Studies released at a conference in the French capital.

"I am totally convinced that click and mortar is the future," said Georges Plassat, the head of world number two retailer Carrefour, referring to the combination of online sales and shopping in stores.

He told the three-day World Retail Congress that more than two thirds of his group's sales are still in-store.

"There is a dream for people working purely in the Internet that they will be delivering everybody on a daily basis a liter of milk. This is totally a dream and could become a nightmare because of the cost of energy."

Kingfisher chief executive Ian Cheshire said Europe's biggest home improvements retailer is overhauling store layout and using space for events like do-it-yourself classes.

"I can't realistically outrange Amazon. What I can do is make my range better curated and framed," he said.

Kingfisher staff also suggest items to people collecting online goods, like brushes and dust sheets with paints, he said.

STORE FOOTPRINT

John Lewis, Britain's biggest department store firm, is a major retailer which is still expanding stores.

"Customers want to combine pure online with visiting stores. Stores have a big role to play," Mark Lewis, head of John Lewis Online, which already accounts for more than a quarter of group sales and is expected to eventually hit 40 percent.

Lewis said more than two-thirds of sales involved stores and online, such as collecting Internet orders in-store, researching online or scanning items with smart phones to read reviews.

Not all players have responded to the Amazon threat as fast as John Lewis, whose early move into e-commerce helped it weather the recent downturn better than rivals.

"Retailers who thought they were protected are having to respond," said Tony Stockil, head of retail consultancy Javelin.

Graham Cooke, head of Qubit, which helps firms analyze their website traffic, said many retailers still had to remove artificial barriers between online and offline businesses.

Simon Calver, the former head of online movie rental firm Lovefirm, now turning around British mother and baby products retailer Mothercare, has been overhauling stores as showcases and theatres of products, most of which he said are researched online before a shopping trip.

"There will always be stores," he said, adding he sees under-served pockets of Britain where Mothercare could still open branches, even as it slashes total shop numbers.

Jacques-Antoine Granjon, boss of French e-commerce firm Vente-privee.com, said formerly pure online players were having to learn from traditional retailers and predicted that fashion e-tailer ASOS would eventually open its own stores.

"It is the end of pure players, they are finished," he said. "The future is multi-channel and cross-channel. E-commerce is just a new distribution channel."

(Reporting by Patrick Lannin)

By Emma Thomasson and Dominique Vidalon

Stocks treated in this article : CARREFOUR, ASOS plc, Kingfisher plc, Mothercare plc, Amazon.com, Inc.