Accusing Obama of sitting on the sidelines during bipartisan debt talks, Christie said, “If that’s your attitude, Mr. President, what the hell are we paying you for?”

The stark contrast between then and now demonstrated how the bond nurtured by the odd couple after Hurricane Sandy has unraveled — and been replaced by a feud between two politicians who no longer stand to benefit from the appearance of a close partnership.

At the root of recent tension is a disagreement about relief for New Jersey residents affected by the hurricane, which hit in October 2012. Christie in recent days has blamed Obama and his administration for getting in the way of help reaching the state.

Christie’s frustration has become a theme of his town-hall meetings, and he has called FEMA — the Federal Emergency Management Agency — the “new F-word.”