298. Unauthorised leases granted after the mortgage.

A lease granted by a mortgagor after a mortgage without statutory or express power is good by estoppel between mortgagor and lessee1, but void as between mortgagee and lessee2, although a mortgagee who purchases the equity of redemption may be bound by tenancy agreements made by the mortgagor3. The lessee is not protected against a legal mortgagee by the rent restriction legislation4. A lease which is void as between the mortgagee and lessee is void against a purchaser on the mortgagee exercising his power of sale without any express assurance of the mortgagee's rights against the mortgagor