The "cowboy" developers who illegally knocked down Carlton's Corkman Irish Pub have apologised for their demolition of the 159-year-old hotel, and have said they will rebuild it.

They have also hired well-connected Labor lobbyists and spin doctors to help them negotiate with the Andrews government.

Late on Thursday afternoon, Raman Shaqiri and Stefce Kutlesovski sent a letter to Planning Minister Richard Wynne saying they were sorry for knocking down the historic pub without warning.

"We want to make absolutely clear that we will rebuild the building at our expense," the pair said in their letter, which was given to The Age by Labor-linked lobbyist Erik Locke and former Labor lord mayoral candidate Will Fowles, whose firm Piper Communications is also working for them.