Heavy high street discounting and unemployment among younger shoppers is likely to slow the meteoric growth of Asos.

Chief executive Nick Robertson said that although the e-tailer would continue to expand, growth would not be near the 100 per cent levels that it achieved in its full year to March 31.

In the 13 weeks to June 26 sales were up 52 per cent year on year. “We are still up and we plan to be up next year, just not as much,” said Robertson. “Job insecurity has to be a worry and I suspect that people are holding back.”

Pre-tax profits for the year soared 93 per cent to £14.1m and Asos said that its key growth area for the coming year would be in international markets, in which sales rose 303 per cent to £32.2m.

The overseas business is still growing at about 150 per cent and there are plans to launch country-specific websites. Tailored websites are likely to be launched first in Asos’s biggest markets, such as the US, France and Germany.

Numis analyst Andrew Wade said that the international growth was particularly encouraging as it had been achieved with almost no marketing. “With Jon Kamaluddin turning his focus to his role as international director, we expect this element of the business to move ahead rapidly and in a low-risk manner,” he said.

Robertson said that Asos would continue to pursue new international brands to sell online in the UK, such as Mango and Gap, which it has already secured.