Trinity Mirror's financial adviser NM Rothschild is sending out NDAs to more than 20 interested parties this week.
The group has decided to keep the assets in Wales, the North East, the North West, Scotland, as well as national titles the Daily Mirror and the Sunday Mirror.
Net cost savings last year were £5 million above target at £20 million.
Throughout the year, the company launched 240 websites and six new newspaper titles and also acquired estate agent directory Email4Property in May 2006.