The two nations which remain technically at war opened negotiations in October after quiet US diplomacy, seeking to clear the way for offshore oil and gas exploration sought by both.

"Regrettably, despite goodwill on both sides, the parties remain far apart," said Pompeo, who has one month left in office after President Donald Trump's electoral defeat.

"The United States remains ready to mediate constructive discussions and urges both sides to negotiate based on the respective maritime claims both have previously deposited at the United Nations."

The Trump administration has heralded major progress in its waning days in Israel's relations with the Arab world.

Since October, four Arab nations have agreed to recognize the Jewish state.

The latest session of talks between Israel and Lebanon was put off after the Jewish state accused its neighbor of inconsistency.

The two nations have been negotiating based on a map registered with the United Nations in 2011, which shows an 860-square-kilometer (330-square-mile) patch of sea as being disputed.

But Lebanon considers that map to have been based on wrong estimates and now demands an additional 1,430 square kilometers (552 square miles) of sea farther south, which includes part of Israel's Karish gas field, according to Lebanese energy expert Laury Haytayan.