deferred tax – tax rate

What tax rate do you apply to the deferred tax? do you apply the current corporate tax or the next year corporate tax?

E.g If the new corporate tax rate of 25% is enacted as law when the government approves it, and the approval happened before the year end, do you apply the 25% because the new tax rate has become the new corporate tax from this year?

if it wasn’t approved till after the year, then would you use the old corporate tax rate?

Thank you in advance