Minoan Group said its travel business has been negatively affected by the outcome of the UK's non-binding Brexit vote to quit the European Union, weakness in sterling and the decline of tourism in Turkey.
"Accordingly, profits for the current year will not meet market expectations," it said in a statement.
"In respect of our Greek project, the Court hearing of the appeals against the issue of the Presidential Decree remains scheduled for 16 September.
The company concluded that the effects of the Brexit vote and the situation in Turkey would be "temporary in nature and that the outlook for future growth is healthy."
"We reported in the Group's Interim Statement that we were very pleased that our Travel Business showed a growth in gross profit of circa 19% in the first half of the year, but that we were concerned as to the impact of the Brexit vote," the company said.
"In overall terms, the Brexit vote, including the decline of Sterling together with the ongoing situation in Turkey where tourism is down by 40%, has had a material effect, in particular in our market for late holidays (due to the reduced availability of less expensive product).
"In the past few months the impact on gross profit has been running at approximately £100,000 per month.
"Whilst this will have a significant effect on profitability in the current financial year, the Board is encouraged by the trend in forward bookings for 2017 which show a return to a rate of growth ahead of current market indicators at 8%.
"As reported in the Group's Interim Statement, the Court hearing of the appeals against the issue of the Presidential Decree ("PD") is scheduled for 16 September 2016.
"This is the first date in the new judicial year following the Court's Summer Recess and our advisors have confirmed that there is no reason to expect a change to this timetable. The Court process is that, following the hearing, the Judges meet to determine the merits, or otherwise, of the arguments put forward.
"the Board is encouraged by the fact that the Court has already reviewed the PD on two occasions when it was judged to be lawfully proposed by the unanimous opinion of the Plenum of the Court and, accordingly, is hopeful that a positive decision will be announced quickly."