The proposal, which has been put forward by Labour's high command, would mean Mr Blair carrying on until late next May or early June after an election that would take between eight and twelve weeks, a report carried in 'The Times' said.
The report comes while Labour MPs and ministers continue to speculate whether there will be a heavyweight challenger to Gordon Brown.
Alan Johnson, the Education Secretary, has become the bookmakers' second favourite to replace Tony Blair. In the past he has indicated his interest in the deputy leadership's post but is clearly not yet ruling himself out for the top job.
However, it is speculated that an announcement by Mr Blair in March could give a big boost to the chances of Mr Brown, whose Budget would be dominating news events.