Logistics group Christian Salvesen - which has a major operation in the West Midlands - has warned of a potential brake on profits after hauliers in Spain began strike action over fuel prices.
Salvesen said there could be a negative impact on second half results amid uncertainty about how long the nationwide action will last.
As well as the strike by the Spanish Transport Federation, which began yesterday and involved Salvesen subcontractors, the company said volumes within its UK industrial-based business were under pressure.
"Profit before taxation for the first half is expected to be broadly in line with expectations with most of the company's operations performing well, " Salvesen told shareholders.
"The exception has been UK Industrial, where transport volumes for existing customers were lower and the start up of some new contracts occurred later than expected.
"Existing customer volumes are difficult to predict, but new customer volumes are expected to improve in the second half and this growth, together with additional cost reduction initiatives is expected to improve profits in the second half."
The United Kingdom industrial division includes customers in the automotive, chemical, DIY and paper and packaging sectors. Other parts of the company have performed well, with contract retention rates remaining high and business losses kept to a minimum as Salvesen attempts to maintain its recent signs of recovery.
"During the first half, the company has continued to show good progress in overall new business wins, which are on track to match last year's improved performance," it added.
" In addition, contract retention rates remain high and lost contracts have been minimal."
Analysts had been hoping profits would rise to £17.8 million for the full year, but it is expected that the Spanish strike may cause this to be trimmed back towards last year's £17 million.
Shares fell by more than four per cent to 66.5p following the warning.
The Northampton-based group, which employs more than 13,000 people and operates in six European countries, including France and Portugal, has a new management team which has sought to stem the loss of contracts and focus on core logistics activities in the transport and food and consumer sectors.
The operations have been reorganised to focus on these two areas while a decentralised structure has been established to speed up growth.
"This restructuring, which will generate annual savings of almost £2million, will fund higher spending on sales and marketing.
"The one-time cost of this change will be approximately £1 million and will be recognised during the second half," Salvesen added.
Major customers of the company have included Marks & Spencer, Asda and Michelin.
The company will release its interim results for the six months ended September 30 on December 6, together with an update on its long term plans.