KIEV, April 4 - Naftogaz Ukrayiny has brought in consulting firm McKinsey & Co to advise on selecting a lead manager for the company's planned initial public offering, Energy and Coal Industry Minister Yuriy Boyko said in an interview with the television channel Inter.

Boyko said that Naftogaz Ukraine hopes to raise a least $5 billion-$6 billion from the sale of up to 25% of its shares.

"This is based on the most pessimistic forecasts," he said, adding that an earlier sounded estimate that put the Ukrainian holding at $10 billion-$12 billion is clearly undervalued.