It is not prohibited. But the change has to be as per IAS 8.
Noted that IAS 40 says
"IAS 8 Accounting Policies, Changes in Accounting Estimates and Errors states that a
voluntary change in accounting policy shall be made only if the change results
in the financial statements providing reliable and more relevant information
about the effects of transactions, other events or conditions on the entity’s
financial position, financial performance or cash flows. It is highly unlikely that
a change from the fair value model to the cost model will result in a more