Thousands of Palestinian Authority civil servants have not yet received their May wages because Israel is late in transferring tax revenues due under an agreement between the two sides, a PA official said Sunday. Jamal Zakout, a PA government spokesman, said Israel was meant to transfer $78 million at the end of May. The money goes toward paying salaries of around 150,000 Palestinian civil servants. "We were informed there was a technical delay," Zakout said. He said Palestinian Authority Prime Minister Salaam Fayad's office expected the money to arrive during the coming week. Lee Gat, spokeswoman for Finance Minister Ronnie Bar-On, said on Sunday that the transfer was made during the past few days. Fayad staffers suspect that Israel delayed the transfer as a deliberate response to a public call by Fayad this week for the European Union to reject Israeli attempts to upgrade relations with the bloc. The unusual move from the normally discreet Fayad upset Prime Minister Ehud Olmert, who expressed his "grave concern" over the matter. Israel, which has strong trade relations with the EU, is looking for closer cooperation in research and political and economic areas. Israel also is seeking membership in the 30-member OECD, which champions democracy and free market economy. The rival Hamas government in the Gaza Strip, boycotted by international aid donors, has already paid the May salaries of its 20,000 staff. Hamas obtains its funds through smuggled cash, some of it originating from Iran and from ad-hoc taxation of Gaza residents.