Two of the largest publicly traded health insurers will team up to sell Medicare Advantage plans to employers that offer retiree coverage.

Cigna and Humana say they plan to collaborate on a deal that provides Humana's Medicare Advantage insurance to employers in Cigna's customer base. Cigna will then manage the accounts.

The companies will split revenue from the deal, which they say blends strengths of both insurers.

Humana offers dozens of Medicare Advantage plans nationwide, while Cigna offers coverage to employers in every state.

Medicare Advantage plans are privately run versions of the government's Medicare program. They provide health coverage for the elderly and disabled.