At its 28th meeting, the General Conference on Weights and Measures (abbreviated GCPM in the source) decided that the practice should end.
The group said a negative leap second, which would remove a second and has never been used, could cause anomalies and disruption in critical infrastructure that is largely unprepared for it.
In its resolution, the body said preparing for a negative leap second would require financial investment from industries that depend on time synchronization, comparable to what they spent on the millennium bug.
Historians put the global cost of Y2K remediation at $300 billion to $600 billion, though many people think that money was poorly spent.
The body also cited the growing role of internet of things devices, smart grids and distributed sensor systems, which raises the risk of malfunctions whenever a leap second is inserted, especially a negative one.
It added that service providers handle leap seconds in different ways to avoid sudden time steps, which produces inconsistent timing between systems.
The Register offers one example of how things could go wrong: digital certificates carry a "not before" time, and systems may reject a certificate that appears to be from the future. If a major internet provider's modems failed to handle a leap second, the network could in theory decide its own customers are untrustworthy. The replacement approach, called "Continuous UTC," will let the astronomical time scale UT1 and Coordinated Universal Time (UTC), the standard people use to set clocks, drift apart by up to 3,600 seconds. It is due to take effect next year.
