Sanader made the statement in response to questions at a joint press conference after a meeting with European Commission President Jose Manuel Barroso.
Sanader recalled that Croatia had begun EU membership talks during the British presidency of the EU, and that during Blair's term as prime minister Croatia and Britain had signed an agreement on a strategic partnership whose purpose was to help Croatia on the road to the EU.
"We're losing a great friend, but I'm sure his successor will continue the same policy," the Croatian prime minister said.
Blair announced earlier on Thursday he would resign as prime minister on June 27.