Green Scottish MSP Patrick Harvie has agreed to sign a pressure group's pledge not to co-operate with the national ID card scheme.
He will take the pledge, along with others, at a meeting of the NO2ID pressure group in Edinburgh tomorrow.
A similar meeting is being held by NO2ID this evening in central London, where others will take the pledge not to co-operate with the ID scheme.
The group has asked people to pledge not to register for an ID card or supply any personal information that would be stored on the government's proposed National Identity Register.
This includes applying for future documents and government services linked to collecting information for the proposed national database.
The Edinburgh meeting takes place tomorrow at the Quaker Meeting House on Victoria Terrace.