A search will resume on Monday morning for a man who was reported missing after being swept into the ocean in Newcastle.

Emergency services were called to Nobbys Beach around 7pm on Sunday following reports two 23-year-old men were at a rock face near the ocean when a wave knocked the pair into the water.

Bystanders assisted one of the men to safety, but the second man could not be located.

A search by Water Police, a rescue helicopter and Surf Life Savers was called off about 9.40pm due to hazardous conditions.

AAP