The Uniting Church in Australia will stop investing in corporations that extract dirty or risky fossil fuels, saying it must do its part to support small island states at risk over global warming.

The national Assembly Standing Committee resolved this week to divest itself of fossil fuel-based company investments. Uniting Church president Reverend Professor Andrew Dutney called the decision an important act of public witness.

"As Christians we are called to respect and care for the whole of creation," Reverend Professor Dutney said, in a statement

"With national governments reluctant to take difficult decisions, it falls to us as members of the body of Christ to show leadership in taking action to reduce damaging pollution."

The move follows similar decisions by the Synod of NSW and ACT in April last year and the Synod in Victoria and Tasmania in February.