Contractor Leighton Holdings has moved to stem a blowout in customers that owe it money, which has put its balance sheet under pressure as the mining boom fades.
It has suffered a $600 million rise in the June half alone, with trade and other receivables on its balance sheet hitting $4.4 billion, up from $3.8 billion a year earlier.
About half the total is owed by oil and gas companies, it said, calling the increase "unacceptable". Since then, there has been an improvement, with some payment received for a project in Iraq following a recent visit by the chief executive, Hamish Tyrwhitt. Iraq accounts for two of the top three outstanding contracts where payment is due, the company said.
Chief financial officer Peter Gregg said the largest was the $1.85 billion Gorgon jetty project in Western Australia, with the delay payment "related to time and weather".
In other cases, there are disputes with mine projects in Indonesia, while litigation is under way in Singapore, London and Brisbane, with the first arbitration outcome not expected until later in the year.
Mr Tyrwhitt said LNG projects could take nine to 12 months for payment to be received, for example, while contract variations have slowed payment for other projects.
"It's a difficult problem to solve," Mr Gregg said.
The rise is due partly to larger contract sizes coupled with project delays, with the decline in the value of the Australian dollar also pushing the figure up.
The second-slowest payers are coalminers, partly due to the downturn in coal prices. But the largest area of reluctant payers is in the Middle East and North Africa, with 59 per cent of the amount due not expected to be repaid for longer than two years, up from 51 per cent six months earlier.
Mr Tyrwhitt said "detailed plans" were in place to drive the recovery of receivables, with as much as $500 million of the rise in the amount outstanding expected to be repaid by year end.
"Having provided the hard number, it must have some confidence to achieve this. Nevertheless, it looks an ambitious target," NAB said in a note to clients.
The blowout came as Leighton lifted its June-half net profit to $360.2 million from $105.9 million a year earlier, thanks largely to a $215 million gain from selling off equity in a telecommunications unit. Leighton reiterated its full-year net profit guidance of $520 million to $600 million.
The higher profit saw a hike in the interim dividend to 45¢ from 20¢ paid previously.
As part of a series of measures to double profit margins, Leighton is to establish a centralised unit to own its extensive fleet of equipment, which could take in external shareholders, it said.
"Effectively, we could become a Coates to ourselves," Mr Gregg told analysts, referring to the equipment hire company and the plans for the new internal unit "fleetco".