On Tuesday morning Conservative leader David Cameron called on the Liberal Democrats to make a decision between the Tories, with whom they have been in negotiations since the hung parliament result became clear last week, and Labour, with whom talks started on Monday.
Many commentators believe the timing of Mr Brown's announcement was aimed at torpedoing the Conservative-Lib Dem deal and removing one of the key obstacles to agreement between Labour and the Lib Dems.
Mr Brown has said he would like a new Labour leader in place before his party's October conference. He has urged potential leaders not to publicly announce their bids until a deal has been brokered but possible candidates are believed to include David and Ed Miliband, Ed Balls, former health secretary Alan Johnson and last health secretary Andy Burnham.
MPs returned to Westminster on Monday, although Parliament does not actually resume for business until 18 May.
Keep an eye on Healthcare Republic for news of the deal and what it will mean for those working within the NHS.