"Provided that such a policy shall not be required to cover" liability in excess of$50,000 . It is evident that liability "required to be covered by a policy" relates to liability which is covered by the terms of a policy that insures the holder in respect of liability for bodily injury, and which need not exceed$50,000 . In short, the insurers' liability to a third party is determined, subject to the permissible limit of liability, by reference to what that policy which rendered the insurer liable to his insured in respect of the accident was required to cover. Because the policy in question was not required to cover liability in excess of$50,000 , that is the applicable limit. In Harker v. Caledonian Insurance Co. [1980] 1 Lloyd's Rep. 556 the House of Lords held that the wording of the similarly worded Honduran Ordinance was clear and free from ambiguity, and affirmed the judgment of the Court of Appeal upholding the decision of Donaldson J. that in a direct action under that Ordinance the insurers were entitled to limit in accordance with that Ordinance their liability to a driver killed in a collision with the assured. Under the Honduran Ordinance sections 4(1)(b) and 20(1) corresponded with sections 4(1)(b) and 8(1) of the Trinidad and Tobago Ordinance respectively. Of the Honduran Ordinance Lord Diplock said at page 558:- "