Spanish infrastructure firm Ferrovial it plans to sell a ten per cent stake in airports operator BAA in order to finance new investments and pay off debt.
Ferrovial shares opened up four per cent and bucked a 0.35-per cent slump by the Madrid bourse.
"The beginning of this process is within the policy framework of deriving value from Ferrovial assets, taking advantage of the financial solidity achieved at BAA," the company said in a brief regulatory filing.
A company spokesman said Ferrovial, which owns 55.87 per cent of BAA, hoped to settle a deal to sell the stake some time in 2011.
"Our aim is to continue to be a strategic partner and leading shareholder in BAA," the spokesman said.
BAA runs airports including Heathrow, Stansted, Glasgow and Edinburgh.