He was asked:

A man appointed another as his agent to rent property for him, let property on his behalf, sell on his behalf, and purchase for him. The agent rented a share in a village for his principal for a specified term under a valid, binding lease. He then agreed to cancel the lease during its term, although the principal had not authorized him to agree to its cancellation. Is this cancellation by mutual agreement valid? Does the lease remain valid as originally concluded, with its benefits belonging to the principal? Is the lessor entitled to the rent in these circumstances?

He replied:

Praise be to Allah. If the tenant cannot collect the rent to which he is entitled, he may cancel the lease, just as when a purchaser cannot recover the price, if he requests cancellation in these circumstances. As for the tenant’s leasing to the agent, he had done what was required of him. This is not one of those permissible cancellations by mutual agreement that require the principal’s permission. And Allah knows best.