The largest-ever infrastructure investment in Israel’s history—possibly $10 billion—has been halted and could face delay of at least a year following a March 27 domestic court ruling that rejected the framework for the U.S.-Israeli developers of the Leviathan offshore gas field. Its estimated 22 trillion cu ft of natural gas was seen as key to Israeli energy self-sufficiency and to regional gas export deals being negotiated.

Israel’s high court rejected a controversial government clause, adopted last year, that granted the developers, Houston-based Noble Energy Inc. and its Israeli partner Delek Group, a 10-year guarantee of regulatory stability. Judges gave the parties one year to come up with an alternative arrangement. Environmental and other opponents brought the case to overturn the framework. The decision is “disappointing,” said Noble Energy. “Development of a project of this magnitude, where large investments are to be made over multiple years, requires Israel to provide a stable investment climate,” noted CEO David Stover in a statement, adding that it was up to the government to find a solution quickly.