Income tax expense comprises current and deferred tax. Current tax and deferred tax are recognised in profit or loss except to the extent that it relates to a business combination, or items recognised directly in equity or in other comprehensive income.

Current tax is the expected tax payable or receivable on the taxable income or loss for the year, using tax rates enacted or substantively enacted, at the reporting date, and any adjustment to tax payable in respect of previous years.

The tax base of an asset is the amount that will be deductible for tax purposes against any taxable economic benefits that will flow to an entity when it recovers the carrying amount of the asset. If those economic benefits will not be taxable, the tax base of the asset is equal to its carrying amount.

The tax base of a liability is its carrying amount, less any amount that will be deductible for tax purposes in respect of that liability in future periods. In the case of revenue which is received in advance, the tax base of the resulting liability is its carrying amount, less any amount of the revenue that will not be taxable in future periods.

Deferred taxation is provided in full, using the liability method, on temporary differences arising between the tax bases of assets and liabilities and their carrying amounts in the consolidated financial statements. However, if the deferred taxation arises from initial recognition of an asset or liability in a transaction other than a business combination, that at the time of the transaction affects neither accounting nor taxable profit or loss, it is not accounted for. Deferred taxation is calculated using rates that are expected to apply when the related deferred asset is realised or the deferred taxation liability is settled.

Deferred taxation assets are recognised to the extent that it is probable that future taxable profit will be available against which the temporary differences can be utilised.