In 2008, the exchange of goods between these two neighbours exceeded EUR 2.5 billion.
Participants in the Ljubljana event said that economic cooperation was successful.
Addressing the meeting, Slovenia's President Danilo Tuerk said the two countries' border issue could be solved in several months' time to the satisfaction of both sides.
However, Tuerk said that Slovenia was disappointed by its eastern neighbour's conduct and that the Slovenes "feel that the Croatian side is showing reservations and making proposals which hinder and presumably make it impossible for realising the European Commission's idea regarding mediation as the method for solving the border dispute."
"The problem of the border (demarcation) should be considered in its entirety. One should realise that it requires creative solutions. When it comes to the border at sea, one cannot ignore the Slovene interest which is legitimate and natural and which requires (Slovenia's) direct access to the open seas," he said.