Read all about it: Trinity Mirror and Express Newspapers 'in merger talks' for second time

Two of Britain's biggest newspaper groups are reportedly holding talks over a potential merger deal.

Express Newspapers, owned by Richard Desmond, and Trinity Mirror, the owner of the Daily Mirror, Sunday Mirror and Sunday People, are understood to have reignited talks, with an official announcement to be made on Tuesday (10 January).

The two companies held discussions about a potential deal two years ago, but they fell through due to disagreements on pricing and substantial pension deficits on the Express titles.

At the time, the deal focused on a full sale of the Express newspapers, including the Daily Star, to Trinity Mirror. Exactly what is being negotiated in the latest round of talks is as yet unknown.

However, a source with knowledge of the negotiations told the Guardian that the talks are thought to have started late last year. It is believed they were focused on Trinity Mirror potentially taking a minority stake in Express Newspapers. Such a deal could mean merging back-room staff and sales operations, leading to significant savings.

The talks come as UK national newspaper publishers including Trinity Mirror, the Telegraph, the Sun and Times owner News UK and the Guardian explore combining print and digital sales to fight back against the growing dominance of Google and Facebook. Express Newspapers is not involved in this initiative, called Project Juno.

When the last negotiations between Desmond and Trinity Mirror broke down, Trinity Mirror instead secured a £220m ($267.5m, €252m) deal to buy the regional newspaper publisher Local World.

It added more than 100 regional newspaper titles to Trinity Mirror's existing 130 local papers.