Qataris are set to snap up a fifth of BAA for £900m

The Qatari sovereign wealth fund has agreed to buy a fifth of BAA, the Heathrow Airport operator, for £900m in a transaction involving deals with three of its key shareholders.

Qatar will pay Spain's Ferrovial £478m for a 10.62 per cent stake in BAA, which also operates Stansted, Glasgow, Aberdeen and Southampton airports, leaving the Spanish infrastructure investor with a 39.37 per cent holding.

It will also buy a 5.63 per cent stake from Britannia Airport Partners and 3.75 per cent from GIC Special Investments, Singapore's sovereign wealth fund.

The share acquisitions are the latest in a series of deals as Qatar has spent its oil and gas wealth on substantial stakes in British household names such as Barclays, Sainsbury's, Harrods and Canary Wharf. Qatar's holdings also include nearly 11 per cent of Xstrata's shares and its threat to derail the miner's proposed merger with Glencore in search of a higher price represents a huge blow to the chances of the deal going through.

A spokesman for the Qatar fund said: "Qatar Holding maintains its view that the United Kingdom remains an attractive investment destination and there is long-term fundamental strength in the British economy.

"This acquisition is a key element in our exposure to the infrastructure sector, and helps to further diversify Qatar Holding's global investment portfolio," the Qatar spokesman added.