U.S. consumer confidence retreated a bit in August as optimism on the present situation improved to its highest since late 2000, offsetting a weakening in the outlook on economic conditions, the Conference Board said on Tuesday.

The group's index on consumer confidence slipped to 135.1 in August from an upwardly adjusted 135.8 the month before.

Analysts polled by Reuters had forecast a reading of 129.5 for August.

"Expectations cooled moderately, but overall remain strong," Lynn Franco, Conference Board's senior director of economist indicators, said in a statement. "While other parts of the economy may show some weakening, consumers have remained confident and willing to spend."

She cautioned that if the recent escalation in the trade tensions between China and United States persists, consumer expectations will likely dampen.

The survey's expectations index fell to 107.0 from a revised 112.4 in July.

On the other hand, the present situation gauge rose to 177.2 from 170.9. The latest figure was the highest since 179.7 recorded in November 2000, the Conference Board said.