Around 200 campaigners are expected to protest outside the Senedd later against so-called 'fracking' in Wales.
Hydraulic fracturing involves pumping high pressure fluids into shale rock to recover gas and oil.
Campaigners 'Frack-Free Wales' say they have "grave environmental concerns" that the methods "are unsafe to our future generations."
They are planning to hand in a letter, addressed to the First Minister Carwyn Jones.
It is thought there is a substantial amount of gas under parts of South Wales.
The most controversial fracking issue here has centred around an application to test drill for shale gas at Llandow in the Vale of Glamorgan.
More top news
Professor Roger Scully of Cardiff University analyses the results of the latest Welsh Barometer Poll
Becoming cloudier from the north and west during the evening but some places continuing to see some clear spells
A council in Wales has had to pay more than £8,600 to end a hire contract for a Porsche its former boss used to drive.