Washington/New York (dpa) – The United States urged Greece and Macedonia on Tuesday to resolve their dispute over the latter’s name before the NATO summit in Romania next month.

"The time factor is a forcing event and … they should be coming together to work this out before we get to NATO," White House spokeswoman Dana Perino said.

The confrontation between the two countries has threatened Macedonia’s prospects for joining the alliance. Greece, a member of NATO, promised to veto Macedonian membership unless the matter is resolved.

NATO was expected to invite Macedonia to join at the summit in Bucharest April 2-4.

The United States in 2004 recognized Macedonia under its constitutional name, the Republic of Macedonia. The decision irked Athens, which believes the name implies territorial claims to parts of Greece.

Macedonia had been known internationally as the Former Yugoslav Republic of Macedonia, or FYROM, since separating from Yugoslavia in 1991. International organizations and most countries continue to use the earlier name.

The United States has backed a UN effort to resolve the matter and would likely adopt any new name agreed to through the UN process.

The UN mediator, Matthew Nimetz, recently proposed alternates like New Republic of Macedonia, Upper Macedonia or the Republic of Macedonia (Skopje).

Greek and Macedonian representatives met with Nimetz in New York on Tuesday for further negotiations. The mediator told reporters the two countries were unable to reach a compromise.

[Copright dpa 2008]