The late president of Croatia, Mr Franjo Tudjman, stashed millions in siphoned funds in an Irish bank, according to Channel 4 News.
The information emerged when the Croatian government released transcripts of secret tape recordings made by Mr Tudjman.
In one exchange a finance minister informs Mr Tudjman that the profits from the sale of the telephone network have been lodged with an Irish bank.
The transcript says: "Mr President, I have put the money aside for the summer because I think we need it. We have to prepare for the upcoming elections. I put it in an Irish bank. Only you and I know about this."
The Croatian government said it was contacting "a number for foreign institutions" in a bid to recover the stolen funds. Mr Tudjman is believed to have pocketed at least a tenth of the £1 billion from the sale of the telecoms network.
The tapes also implicate him in war crimes including a secret pact with Slobodon Milosevic to divide Bosnia and eliminate its Muslim population.