"I will resign on Jun 24", Mukherjee told reporters here before leaving for his ancestral house in Birbhum district.
Earlier, sources had said that Mukherjee is expected to file his nomination papers for the Presidential election on Jun 28.
Four sets of nomination papers, each having 50 proposers and seconders, are being readied for the nomination, Parliamentary Affairs Minister Pawan Kumar Bansal had said recently.
Besides Prime Minister Manmohan Singh and UPA Chairperson Sonia Gandhi, several Union ministers as also leaders of constituent parties of UPA are expected to be the proposers and seconders of Mukherjee's candidature for the Jul 19 election.
As part of preparations, MPs of constituent parties of UPA and supporting parties have been asked by Mukherjee's election campaign managers to sign the nomination papers kept in Parliament House.