Signet Group Plc, London, the world’s largest retail jeweler, said on Thursday surging sales in its UK and U.S. markets helped propel a 6% increase in first quarter pre-tax profits, Reuters reported.

Signet said pre-tax profit for the first quarter to April 28, 2001, rose to 17.9 million pounds ($24.92 million) from 16.9 million a year earlier and group “like-for-like” sales rose by 3.4%, Reuters reported.

The news boosted the shares, which rose 5.6%, its highest level in 10 years, Reuters reported.

In the UK, where Signet operates the Ernest Jones and H. Samuel stores and which represents 28% of the group’s annual sales, like-for-like sales rose 10.9% and the gross margin was similar to last year’s level.

In the U.S., where the group trades as Kay Jewelers and Jared — The Galleria of Jewelry, like-for-like sales rose 0.8% and the gross margin improved slightly compared to the same period last year, the company said.

“In the U.S., our business again demonstrated its fundamental strengths by outperforming the jewelry sector and gaining market share in a very difficult trading environment,” said Group Chief Executive Terry Burman in a statement.

He said like-for-like sales since the quarter end had continued at a level broadly similar to April.

“In the UK, the 11% increase in like-for-like sales was at the upper end of the retail sector’s performance and the division made a profit in what is normally a loss making quarter,” Burman said.

JCK