The court can defer the payment of interest on costs under the Judgments Act 1838 where there are real issues of proportionality and reasonableness, particularly if large sums are at stake. The likely existence of such issues was the reason for limiting a payment on account to 50 per cent and it also justified a 4 month postponement of the start of the higher judgment rate interest. The US Prime rate, currently 3.25 per cent, not the Judgments Act rate of 8 per cent, should apply to the judgment sum (Standard Chartered Bank v Ceylon Petroleum Corp).