Reuters has struck a commercial deal with the Guardian to sell online ads to the US market.

The global financial news and information company's sales force will be responsible for selling advertising that will be seen by around five million US-based web users that visit the Guardian.co.uk website each month.

Tom Turcan, the general manager at GNM Digital, described the agreement as the "first big commercial step in a continuation of the Guardian's ambition to become a global brand".

The Guardian's US online advertising sales business was previously handled by the ValueClick network.

Turcan said the Reuters agreement would allow for better targeting of high-value advertising, which could also expand to include selling sponsorship packages and special projects.

The Guardian's web inventory will be sold alongside Reuters.com and the recently launched Reuters Affiliate Network, a collection of news websites and blogs that target the valuable business audience.

"By adding the Guardian to Reuters' sales portfolio we are continuing our efforts to provide a range of options for advertisers to access our growing audience of affluent business professionals," said Chris Ahearn, the president of Reuters Media.

The commercial deal builds on the editorial decision by the Guardian to boost the focus on the US market by launching its Guardian America website aimed at north American users.

In July last year Guardian News & Media's website network, struck a deal with online ad technology company Adify to launch a series of advertising networks based around its travel and environment offerings.

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