Last week's announcement that U2 are to contribute €5m to a new music training fund for children has been labelled a "PR exercise" by tax campaigners.

Critics claim it was designed to distract public attention from recent adverse criticism of the band's tax affairs.

As Bono and his bandmates prepare to play the third of their three 'homecoming' gigs in Croke Park tomorrow, John Christensen, international director of the Tax Justice Network campaign group questioned the timing of the announcement.

He claimed it was "all too easy" for bands like U2 to "hand out the goodies and claim full credit for their generosity, whilst behind the scenes using subterfuge to avoid taxes due".

"In this context, donations to a music training fund do indeed look like a PR exercise designed to distract public attention from the criticisms on the tax front," he said.

"Their moves to avoid tax by switching from an Irish to a Dutch base is seen as hypocritical since tax avoidance – whilst legal – is regarded as sharp practice."

However, U2 guitarist the Edge last week said the band had been "looking for some time for a way to get involved in an initiative in music education in Ireland".

"Being around music at a young age was important for us and we were lucky to have it at school," he added.

Under the scheme, U2 will give €5m to the fund, which is being administered by the non-profit organisation Music Network.

The Ireland Fund's international charity has also part financed the scheme, which aims to teach young people to play a musical instrument or to have their voice trained."