Israel's Prime Minister-designate Benjamin Netanyahu has failed to persuade the leader of a center-left party to join him in a national unity government.

Labor Party leader and outgoing Defense Minister Ehud Barak said Monday after meeting Mr. Netanyahu, who heads the nationalist Likud party, that he would rather serve in the opposition.

The prime minister-designate also failed to persuade the head of Israeli's centrist Kadima Party, Tzipi Livni, to join a coalition led by him when they met on Sunday.  Livni is the foreign minister in Israel's outgoing government.

Mr. Netanyahu says he will keep trying to bring Livni and Barak into a broad coalition that he says is necessary to tackle Israel's security and economic challenges.  He has until early April to form a government.

Several European Union officials expressed concern Monday in Brussels that Middle East peace prospects will suffer if Mr. Netanyahu forms a narrower coalition with other nationalist and religious parties.

Czech Republic Deputy Prime Minister Alexandr Vondra said EU relations with such an Israeli government may have a "rough start."  The Czech Republic currently holds the EU's rotating presidency.

Swedish Foreign Minister Carl Bildt said the EU should send a signal that it is unacceptable for Israel's next government to reject previous Israeli peace commitments to the Palestinians.

Mr. Netanyahu's Likud won 27 seats in Israel's 120-member parliament in elections this month, becoming the second largest party after Livni's Kadima, which took 28 seats.

Israeli President Shimon Peres tapped Mr. Netanyahu to form a government last week after determining that the Likud leader has more potential coalition allies.

Some information for this report was provided by AFP, AP and Reuters.