Alternative Networks expects its figures for the financial year to be "somewhat lower than expected", as its full year draws to a close.
In a trading update, the comms VAR blamed the downturn for the year ending 30 September 2016 on the EU referendum, which led to a weaker performance over the summer than expected.
CEO Mark Quartermaine said: "We are disappointed to have seen business uncertainty over the summer in the wake of the EU referendum impact on our Advanced Solutions business, but the pick-up in new business after the summer reassures us that our business remains well positioned to benefit from long-term trends.
"We will update the market in more detail at the time of our full-year results."
As well as the referendum, Alternative blamed its performance on changes to network roaming.
Earlier this year network carriers introduced new tariffs with lower roaming charges, which Alternative CFO Gavin Griggs said at the time would affect the VAR's profit. The trading update, however, claimed that business in the second half of the year has stabilised following the changes.
Alternative also claimed to have a strong pipeline for the next year, partly because some projects have faced delays, meaning they will not be completed before the year end.
The full results for the year are expected to be released on 8 December.
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