The Institute for Supply Management released its manufacturing purchasing managers' index for the U.S. on Wednesday. The index climbed to 53.5 in June from 52.8 in May, exceeding expectations for a gain to 53.1. It was the highest level since January.

A reading above 50 indicates expansion, below indicates contraction.

The increase was driven by higher employment in the manufacturing sector. The employment index climbed to 55.5 in June from 51.7 in May.

The production index fell to 54.0 in June from 54.5 in May.

The new orders index was up to 56.0 in June from 55.8 in May.

The prices paid index remained unchanged at 49.5 in June.