NOTE 24. ADD: In Riverside Housing Ltd v White [2005] EWCA Civ 1385, [2006] 14 EG 176, [2006] HLR 282 (reversed on different grounds by the House of Lords at [2007] UKHL 20, [2007] 4 All ER 97) the Court of Appeal held that an estoppel by convention could not be used to sustain a claim for rent arrears by a landlord against a tenant. In that case the landlord had served a unilateral notice increasing the rent (which it was entitled to do) but the notice was expressed to take effect at a date which was later than that provided for in the tenancy agreement. The Court of Appeal held that the notice was ineffective as a matter of contract and although all of the ingredients of an estoppel by convention were made out, the claim failed on the basis that the estoppel could not be used a sword rather than a shield: see [59] to [67]. In both Baird and Riverside the Court of Appeal confirmed that an estoppel of this kind could only be used as a sword if the House of Lords so decides. Permission to appeal to the House of Lords has now been given.

NOTE 26. ADD: For an example of a case in which promissory estoppel was raised as a defence to a claim for possession see Babar v. Anis [2005] EWHC 1384 (Ch) (Richard Arnold QC). It would be absurd if the outcome depended on whether D had brought a claim for a declaration or whether she based her claim on promissory estoppel rather than proprietary estoppel.