Shares in Hogg Robinson Group (HRG) and easyJet fell sharply after the companies both issued profit warnings.
The travel management company said there was weak demand in some areas and delays in signing customers to its Spendvision expense management business.
A statement by the company said: "As a result of these factors, the Board continues to expect revenue growth for the year ending 31 March 2008 but EBITA is now expected to be lower than the prior year at around 10% below the market consensus of £45m."
HRG said that since its Interim Management Statement in January, "as previously flagged, demand in events and unmanaged SME business has continued to be weak and results in these areas will fall short of expectations."
It said that its Spendvision expense management business had also experienced "some delay in new clients signing contracts to originally expected timescales as well as slower-than-expected implementation of contracts with some recently signed clients."
It said its European re-structuring was progressing well and would cost £2m which was less than expected.It also planned further cuts in costs elsewhere in the Group which would cost around £1m.
David Radcliffe, Chief Executive, said: "This trading setback is disappointing but we are taking, and will continue to take decisive action to mitigate the effects of the economic downturn and to ensure that the Group is positioned well for next year."
easyJet said the price of fuel had risen to "unprecedented levels and if it remains at current levels, naturally easyJet, like all other airlines will incur a significant increase in fuel costs.
Andy Harrison, its ceo said: "First half results will be in line with our expectations, however it is pretty obvious that if the recent significant rise in the fuel price is maintained then our second half profits will be lower than we had previously expected.
"Of course the price of fuel will hit all airlines and we remain convinced that the combination of our new fuel efficient aircraft fleet, together with the proven strength of the easyJet business model will mean that we shall emerge as winners in a high oil price environment."
Europe's second largest low cost carrier said fuel said that in February, "the forward price for jet fuel for summer 2008 was $840 per tonne. Tthe current forward price for jet fuel for summer 2008 is over $1,000 per tonne.
"If current prices were to be maintained there would be an additional second half fuel cost of around £45m, despite easyJet having 40% of its fuel requirements hedged at $750 per tonne.
"It is unlikely that such a large and immediate fuel increase could be mitigated in the short term by revenue improvements and cost actions, therefore pre-tax profits for the full year would be below previous guidance."
HRG shares opened yesterday (March 19) at 54.50p but fell sharply after the company's statement was issued. At close of business, they stood at 41.75p, a drop of 21.23%.
When trading opened today on the London Stock Exchange, they fell again slightly (1.20%) to 41p.
easyJet shares dropped by 9.5% to 339p yesterday but rallied slightly today to 357p.