The Supreme Court agreed Friday to wade into a fight over Congress’ ability to delegate power to federal agencies — opening the next chapter in a decadeslong effort by conservatives and business interests to reduce the power of the federal government.

The cases explore whether Congress violated the Constitution when it allowed the Federal Communications Commission to gather fees to help pay for critical telecommunications services in communities that might not otherwise have it.

The Supreme Court could further weaken the power of federal agencies by agreeing to hear a dispute over a Federal Communications Commission program that requires companies to subsidize telecommunications services in under-served areas.