Group sales for the period were£292.1 million in the 13 weeks to October 30.
In the 39 weeks to the end of October, group like-for-like sales increased by 6 per cent to£963.7 million. In the UK, like-for-like sales at H Samuel were up by 2.9 per cent for the period, while Ernest Jones reported a 6 per cent rise.
Signet group chief executive Terry Burman said: 'In the UK, the softening trend in the trading environment continued during the third quarter, with the upper sector of the mass market being most affected. Diamonds again outperformed other categories at both Ernest Jones and H Samuel.'