Tomasic said that the future of the Croatian people was at stake, recalling that Josipovic and Kosor had the duty to protect Croatia's interests.
She called on them to say exactly what Croatia could expect of its EU membership, and which advantages and disadvantages it would bring to Croatia.
She said that her party was not a Euro-skeptic but a Euro-critic.
Earlier in the day, the treaty regulating Croatia's accession to the EU was signed in Brussels by Josipovic and Kosor and by leaders of the 27 EU member-states.