I didn't expect them to be at daggers drawn over such a trivial thing.

我没料到他们为这一点小事竟会如此势不两立。

《新英汉大辞典》

We are still at daggers with each other.

我们俩仍是势不两立。

youdao

Jack and Peter have been at daggers drawn for a long time.

杰克和彼得长期以来不共戴天。

youdao

One explanation might be that Russia's policymakers are at daggers drawn about the issue.

ECONOMIST: Climate change

In the 1970s Mr Ecevit was at daggers drawn, ideologically and almost literally, with Mr Bahceli's late predecessor, Alparslan Turkes.

ECONOMIST: A swelling tide of nationalism may change Turkish politics

By then the coalition partners could well be at daggers drawn, and the Lib Dems join Labour against an opt-out, in a sign of allegiances to come.

ECONOMIST: Opting out of the EU