WASHINGTON (Reuters) - The International Monetary Fund said on Thursday it was possible that it could decide by year-end whether to participate in a new Greek loan program with IMF funding.

IMF spokesman Gerry Rice told a regular news briefing that any decision depends on discussions now underway in Athens between an IMF mission and Greek authorities as well as parallel discussions with Greece's European lenders.

But Rice noted that the IMF has not changed its position that the fiscal targets for Greece in the current European loan program -- a primary budget surplus of 3.5 percent of gross domestic product by 2018 -- are too ambitious.

The IMF could support a program with a surplus target of 1.5 percent of GDP along with debt relief and fiscal and economic reforms in Greece, he said, adding, "If Greece and its partners want to pursue a more ambitious target, we would need to see the reforms that make it add up."

(Reporting by David Lawder; Editing by Chizu Nomiyama)