"We have agreed to support Ms Merkel and her proposals to be put forward at the meeting of the European Council," Sanader said after the meeting of EPP leaders.
Like the leaders of other party groups represented in the European Parliament, EPP leaders traditionally meet before every EU summit to discuss the same topics on the agenda of the European Council.
The Meise event gathered 11 leaders from EU member-countries, the presidents of the European Council, the European Commission and the European Parliament, and four leaders from European countries that are not EU members, including Croatian PM Sanader.
Sanader said he was "particularly grateful to Ms Merkel for mentioning Croatia in her opening speech".
The PM said that the German Chancellor acquainted EPP leaders with her position on the settlement of outstanding institutional issues, saying that they should be dealt with, otherwise "we will have to tell Croatia in 2009, when the negotiations are completed, that it has done its part of the job, but Europe has not".
"I am an optimist and hope that the EU will solve its institutional issues," Sanader said.