A months-long standoff between Italian and U.S. carmakers Fiat and General Motors ended Sunday with GM agreeing to pay Fiat 1.55 billion euros for the latter not to use its so- called "put-option". The Fiat management agreed to the move at an extraordinary meeting of its administrative board in Turin, with Fiat head Luca Montezemolo declaring himself "relieved" at what would be a move sending a positive signal for the troubled company, state television said. The report said GM had agreed to return its ten per cent Fiat share to the Italians, and the cancellation of two joint ventures for engine and spares production. Fiat workers had threatened to strike and investors had dumped shares earlier in the month in reaction to an announcement Fiat and its U.S. General Motors failed to mend the contractual squabble. The bone of contention was an option allowing Fiat to sell its loss-making car making division to GM. The Detroit-based automotive giant, which agreed to the put-option while buying a stake in Fiat in 2000, has financial difficulties of its own and had lost interest in buying the company. GM managers argue that changes made at Fiat meant the put option was no longer valid - but Fiat asserted its view that the put-option was enforceable. --SP 2329 Local Time 2029 GMT