The NFL on Wednesday sent a memo to teams outlining rules for its offseason programs -- rules the league has decided to impose after failing to reach agreement with its players' union on some key aspects.

The parts of the offseason program that are voluntary under the CBA -- everything but the annual mandatory June minicamps -- will remain so. But while the NFLPA has publicly called for the entire offseason to be conducted virtually in light of the ongoing coronavirus pandemic, the league is telling teams that on-field work will be permitted.

Phase 1 of the offseason program, which reflects what the players requested, will run from April 19 through May 14. All meetings will be conducted virtually, and no on-field work will be permitted. The league says it wants to use this phase to focus on vaccine education efforts and making vaccines available to players, team staff and their families as soon as their various local regulations permit.

Phase 2 will run from May 17 through May 21. It will remain voluntary and meetings will remain virtual, but on-field drills will be permitted under the normal Phase 2 guidelines (which prohibit contact and limit the amount of time spent on the field per day). Annual post-draft rookie minicamps will be held in the week of Phase 2.

Phase 3 will be a traditional Phase 3 that runs from May 24 through June 18 and will include the normal 10 days of voluntary OTA work as well as the mandatory minicamps. Meetings during this phase will be allowed to be conducted virtually or in-person, and applying the COVID-19 rules about testing, contact tracing and limits on the numbers of people allowed in various parts of the team facility.

Players who participate in meetings or workouts virtually will still be entitled to their $250 per diems, which was an important part of the NFLPA's request during the negotiations on offseason programs.

The league will not require players or staff to be vaccinated, but it is waiting to hear back from the NFLPA on its vaccine-related proposal that would ease COVID restrictions on vaccinated players and on teams with personnel that reaches a certain percentage threshold of vaccinations. Under the league's proposal, players who have been vaccinated would be subject to less testing and fewer contact tracing restrictions and would have more freedom of movement around the team facility and outside of it. Teams with players and staff who reach a certain percentage of vaccinations would be subject to more relaxed COVID protocols, as teams in other professional leagues have been.

The NFLPA has said publicly that it believes the offseason program should be exclusively virtual, and it is urging its members not to attend the portions of the program that are voluntary under the CBA. The union does recognize that 203 players have workout bonuses in their contracts that require them to attend offseason workouts to receive those bonuses, and it is not actively discouraging those players from doing so, although the union is trying to articulate a broader message that players should stop agreeing to contracts that include bonuses for attending voluntary offseason workouts.