Microsoft chief executive Steve Ballmer has used his trip to Paris this week to discuss many of his firm's latest ambitions, including how it hopes to innovate in the area of cloud computing.

Speaking to French IT organisation Club Informatique des Grandes Entreprises Françaises, Ballmer discussed Microsoft's plans for virtualisation, enterprise search, distributed computing and new consumer technologies.

But it was in his discussions of cloud computing that he was most revealing, explaining that the firm is set to make a big announcement in the next four weeks regarding a new operating system.

"When we talk about software plus services at Microsoft, we think it means not just how we write things for the internet; it really means a remaking of a number of things," Ballmer said.

"We'll need a new operating system. Just as we have an operating system for the PC, for the phone and for the server, we need a new operating system that runs in the internet.

"I bet we'll call it Windows something. We're going to announce it in four weeks. We might even have a trademark by then. So, for today I'll call it Windows Cloud. And Windows Cloud will be a place where you can run arbitrary applications up in the internet that runs .Net."

As part of this push, Microsoft will do more with .Net, Silverlight, Active Directory and SQL Server, among others.

"Our strategy is to build a symmetric stack: Windows Server, Windows Cloud, Active Directory, Active Directory with Live IDs as an identity system in the internet, SQL Server and an implementation of SQL Server for the cloud," said Ballmer.

"We now have CRM, CRM in the cloud. We have SharePoint; SharePoint in the cloud. We've got Exchange; Exchange in the cloud. And we have big customers already moving in this direction.

"People like Nokia, Coca-Cola and others have signed up to move to Exchange online, SharePoint online. It's not going to be for every one of you. We are glad to work with you in either dimension."

Ballmer also talked about the current economic climate. "Whenever we talk about IT, we've got to have two themes in our minds: doing more with less," he said. "And I would say the pendulum swings between more emphasis on 'with less' and more emphasis on 'doing more'."

Ballmer added that this 'doing more' would be aided with a rapid rate of innovation. "We'll continue to get more powerful computers, more storage, better bandwidth, more disconnected wireless operation," he said.

In order to keep up with advances in hardware, firms will have to innovate, according to Ballmer, offering the example that physical screens will be replaced with touch screens connected to the internet.

"I look out in the audience today. Most of you have either a pencil and a piece of paper or nothing," he said. "Ten years from now, we will actually have digital screens that are this thin, this light, this flexible [like paper]."