Rain caused havoc on major citybound roads around Sydney this morning with a crash on the Anzac Bridge bringing traffic to a standstill.

A Transport Management Centre spokeswoman said traffic was heavy on the bridge all morning but a crash just after 8.40am was the final straw.

Two of four citybound lanes on the bridge were closed while emergency services responded to the crash.

And flooding on the westbound side of the bridge closed one of five lanes at the same time.

A bus breakdown on the Eastern Distributor closed one lane at Woolloomooloo just after 8.30am.