“It remains true, as Lord Roskill has pointed out in Cehave NV v Bremer Handelsgesellshaft m b H (The Hansa Nord)[1976] QB 44 , that courts should not be too ready to interpret contractual clauses as conditions … But I do not doubt that, in suitable cases, the courts should not be reluctant, if the intentions of the parties as shown by the contract so indicate, to hold that an obligation has the force of a condition. ”