雙方談判陷入僵局，在今年五月雙方曾經達成某種協議，但北京卻又突然反悔，

雙方談判陷入僵局，在今年五月雙方曾經達成某種協議，但北京卻又突然反悔，直到今年12月雙方宣稱可望於明年一月簽署第一階段協議

結果 (英文) 1:

The two sides reached an impasse in May this year, the two sides have reached some sort of agreement, but Beijing but suddenly go back on, until the two sides declared in December this year, the first phase is expected to sign the agreement in January next year

結果 (英文) 2:

Negotiations between the two sides stalled and some sort of agreement was reached in May, but Beijing suddenly backtracked until December, when the two sides announced they were expected to sign the first phase of the agreement in January

結果 (英文) 3:

The two sides reached an agreement in May, but Beijing suddenly reneged on it until December, when they announced they were expected to sign the first phase in January