Manufacturing activity in New York State factories rose slightly in July while the prices paid index eased modestly and the inventories index fell into negative territory, New York Federal Reserve said on Monday.

The New York Fed's "Empire State" general business conditions index rose to 26.46 in July from 25.75 in June. Economists polled by Reuters had expected a June reading of 18.00.

The inventories component fell to -19.75 in July from 3.19 in June, while the prices paid component eased to 34.57 in July from 42.55 in June.

The survey of manufacturing plants in the state is one of the earliest monthly guideposts to U.S. factory conditions.