GREENPEACE warned yesterday that it would take action against two major arts venues it accused of using timber from endangered rainforests during recent construction work.

The environmental campaign group claimed the (pounds) 26m Playfair project to refurbish Edinburgh's Royal Scottish Academy used sapele timber, a central African hardwood threatened with extinction due to commercial exploitation.

Greenpeace also claimed the North Edinburgh Arts Centre used merbau, a tropical hardwood regularly sourced from rapidly declining rainforests in Indonesia, where 90% of all logging is illegal. Both developments were backed by millions of pounds of lottery money.

Activists delivered plaques to both sites reading ''National Lottery: Funding Rainforest Destruction'', and urged Edinburgh City Council to ensure future developments use timber from sustainable sources.

Greenpeace last month halted refurbishment work at Kelvingrove gallery and museum in Glasgow for using merbau.

Nathan Argent, Greenpeace forests campaigner, said: ''The national lottery should be using people's money to support good causes, not supporting the destruction of the world's last ancient forests.''

A spokeswoman for the Playfair project insisted that all suppliers used wood from sustainable sources. However, she added: ''On occasion when rare or endangered species, such as sapelle mahogany, was required for matching antique works, either second-hand timber was recycled or, if it was essential to use new timber, a valid licence was sought.''

The North Edinburgh Arts Centre would not comment before consulting architects.