British liberal-leaning broadsheet newspaper, The Guardian, is gearing up for its imminent format change.

Although the paper's owner, Guardian Media Group, remains shy about naming the day for switching to the 'Berliner' mid-size European format, Marketing Week magazine reports that the company has booked substantial TV time for the end of September and outdoor space for October.

The paper has refused to comment on the rumoured £2 million ($3.5m; €2.9m) adspend, save to say: "September is the traditional time for newspapers to boost their marketing and that's what we are doing."

The Guardian's size swap, and that of its Sunday stablemate The Observer next spring, is costing the group around £84m.

Says Bob Phillis, GMG's chief executive: "This landmark decision ... will allow us to leap ahead of the rest of the market and publish the first of a new generation of full-colour newspapers."

The compact trend was set by quality dailies The Independent and The Times, both of which have seen circulations increase since they shrank from their broadsheet size in 2004.

Data sourced from Media Week (UK); additional content by WARC staff