Recent evidence from mooring data in the equatorial Atlantic reveals that semiannual and longer time scale ocean current variability is close to being resonant with equatorial basin modes. Here we show that intraseasonal variability, with time scales of tens of days, provides the energy to maintain these resonant basin modes against dissipation. The mechanism is analogous to that by which storm systems in the atmosphere act to maintain the atmospheric jet stream. We demonstrate the mechanism using an idealized model setup that exhibits equatorial deep jets. The results are supported by direct analysis of available mooring data from the equatorial Atlantic Ocean covering a depth range of several thousand meters. The analysis of the mooring data suggests that the same mechanism also helps maintain the seasonal variability. Key Points The meridional flux of zonal momentum associated with intraseasonal variability acts to maintain lower frequency varying zonal currents in the equatorial ocean, in particular the equatorial deep jets The mechanism is demonstrated using both an idealized primitive equation model and using momentum fluxes computed from mooring data on, and either side of, the equator at 23°W in the Atlantic Analysis of the mooring data shows that the same mechanism also supports the seasonal cycle in the equatorial Atlantic Ocean