The Dáil's spending watchdog is to investigate U2's purchase of a site in Dublin's docklands.

The band is buying a site at Hanover Quay from the Dublin Docklands Development Authority for just 450,000 euro.

The Public Accounts Committee is now asking the authority to explain why the site is being sold so cheaply.

The sale will be one of the authority's last acts before it's wound up in the coming months.

Local Labour TD Joe Costello says the sale was never advertised.

"At this point in time, it hardly seems appropriate that the authority should be disposing of property - certainly in what seems to be a questionable manner, for €450,000."

He noted that, in that area, €450,000 "wouldn't be worth a semi-detached residence."

Committee chairman John McGuinness said the PAC would write to the DDDA next week and ask officials to attend for an explanation on why the site was being sold off so cheaply without a public advertisement.

U2 used to own a studio at 16 Hanover Quay, but were forced to sell it after a Compulsory Purchase Order in 2002 which was to pave the way for a redevelopment of the area.

The DDDA said earlier this week that the site was now being purchased on behalf of U2.