Leeds have confirmed they are in talks with an unnamed group of potential investors.
Speculation has been mounting since the weekend that the club could be the subject of a possible takeover, while it is understood discussions took place in Leeds last week.
A club statement read: "Further to media reports on Tuesday morning, the club can confirm that talks are taking place regarding investment for the long-term future.
"The club has always publicly stated that it would welcome potential investment, but has maintained a belief whereby the quality of the investor is the most important factor in terms of the long-term development of Leeds United.
"No further comment will be made at this stage."
Canada-based Maple Leaf Sports and Entertainment (MLSE), owners of NHL ice hockey franchise Toronto Maple Leafs, have been mentioned on internet fans' forums, but it has been reported the company have denied any involvement in last week's meetings.
Leeds United Supporters Trust also commented on the talks.
A statement on LUST's website read: "We are aware of firm interest from a number of parties looking to buy Leeds United... We understand that Leeds United are in talks with at least two separate groups. We also understand there is one firm bid on the table at present.
"In February we responded to [chairman] Ken Bates' suggestion that we 'put our money where our mouth is' by asking any potential investors, who shared the aims and ambitions of our members and of our Vision Statement, to contact the Trust with a view to working together to take Mr Bates up on his offer.
"We developed a presentation so interested parties could see how working with LUST could help them and have been in contact with a number of people to explore ways of bringing about change for the better at Elland Road.
"As part of this ongoing work we have spoken to two groups who are interested in buying Leeds United. At this stage it is not possible for us to go into details about our conversations with these groups, as with a firm offer on the table we would not want to jeopardise any current negotiations."