Leighton Holdings (ASX: LEI) has confirmed the previously provided guidance for the 12 months to 30 June 2012 for an after tax profit of between $600-650 million after completing a detailed forecasting review across all of its operating companies.

This guidance does not include the estimated pre-tax capital gain of $225 million from the sale of the HWE Iron Ore entities and assets in Western Australia, and the capital gain is subject to final reconciliation, the construction giant said on Thursday.

Leighton CEO Hamish Tyrwhitt signalled further loss at its troubled Victorian desalination plant project, while also highlighting gains across the group’s portfolio.

“In this review we identified further deterioration in the forecast financial position of the Victorian Desalination Project (VDP) which will result in us incurring an additional charge of $192 million.

“But the review also identified gains and opportunities across our portfolio of more than 400 projects including contract mining, offshore oil and gas, and across the civil/building/ infrastructure construction markets. As well as this, there were cash flow and other benefits from the sale of the HWE Iron Ore entities and assets that helped offset the VDP charge,” he said.

Mr Tyrwhitt confirmed that the underlying performance of the company is solid and “this gives us the confidence to provide the guidance that we have.”

“We remain positive about the outlook for the business and, for the 6 month transitional financial year from 1 July to 31 December 2011, the Company expects to report a profit after tax of around $250 million, excluding the capital gain from the HWE Iron Ore business sale.

Looking forward we remain in a solid position with work in hand of around $44 billion as at 30 September 2011 and our core markets continuing to provide substantial opportunities,” said Mr Tyrwhitt.

Leighton will report its quarterly results and update the market at its 50th annual general meeting to be held in Sydney on 11 November 2011.