WASHINGTON — Two senators are warning Secretary of State Rex Tillerson that U.S. diplomatic power is being dismantled on his watch and they’re urging him to reverse course before America’s leadership role in the world is degraded.

In a letter sent Wednesday to Tillerson, Sens. John McCain of Arizona and Jeanne Shaheen of New Hampshire say a hiring freeze in effect since January has almost halted the influx of new foreign service officers. They say shutting off the intake of entry-level officers will inevitably lead to shortages of experienced personnel in the future.

The senators say promotion rates for senior foreign service officers have decreased dramatically over the last year.

McCain is a Republican and Shaheen is a Democrat.

Tillerson is overseeing an overhaul of the State Department’s unwieldy bureaucracy.