The group has started selling mango, passion fruit and lychee-flavoured ice-cream tubs and push-up lollies under plans to grow the tropical drink label.

The Cumbernauld-based group reported a 6.2% rise in pre-tax profits to £33.6million in the year to January 28 helped by strong sales of its tropical brands Rubicon and KA.

This comes as the firm announced further details of plans to open a £40m plant in Milton Keynes.

A spokesman for the group said the move into the frozen market was designed to tap into a growing demand for more exotic ice-cream flavours.

Last year the group closed its a site in Mansfield, Nottinghamshire as it expanded capacity at its main site in Cumbernauld, which is now operating in-line with expectations following production difficulties last summer.

The group, whose brands also include Tizer and St Clements juice, described its overall performance in the past year as 'excellent'.

Revenues rose 6.6% to £237m, and are now up 27.6% over the past three years.

The group's heartland remains in Scotland, where Irn-Bru is popular, but sales in England and Wales grew 8.4% in the year, outpacing growth of 3.4% here.

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