Major League Soccer has delayed the start of the 2021 season by two weeks following extended negotiations over a labor deal between the league and its players, a statement said Wednesday.

The new season was due to kick off on April 3, but will now get under way on April 17 following the marathon talks between MLS and the MLS Players Association over a new collective bargaining agreement.

"We're now going to begin our regular season on April 17," MLS commissioner Don Garber told reporters on a video call. "The CBA negotiatons were extended, so as a result we've moved back the start of the season by two weeks."

The new agreement ratified this week runs through the end of the 2027 season. Players will receive 100% of salaries and bonuses in 2021 despite MLS expecting another year of financial losses because of Covid-19.

The 2020 campaign ground to a halt in March last year after just a handful of games of the season as the pandemic swept across North America.

The league eventually restarted with a World Cup-style tournament in Orlando before the regular season resumed in August.

Garber said dates for the start of pre-season training camps would be announced soon and a 2021 season schedule was likely to be revealed in early March.

Although limited numbers of fans have begun to be allowed to return to some sports arenas in the United States, Garber said it was unlikely MLS would welcome back spectators in large numbers this season.

"We are encouraged by the rollout of the vaccine under the new administration," Garber said. "I was pleased to see fans in the stadium in Tampa for the Super Bowl on Sunday. But I don't have any sense that fans are going to be in our stadiums in large numbers, probably most, if not all, of the season."

Uncertainty also continued to swirl about plans for Major League Soccer's three Canadian franchises -- Vancouver Whitecaps, CF Montreal and Toronto FC.

Travel restrictions related to Covid-19 forced the Canadian teams to play their home games south of the border last year, something expected to be repeated for the 2021 campaign.

"What is going on in Canada is very challenging. We continue to work with our teams, we continue to engage with Canadian authorities," Garber said.

"We're going to abide by whatever the rules are established by Health Canada. As you can imagine all three of our teams are working on alternative plans as to where they're going to be certainly in the short term.

"I feel for our Canadian clubs and I feel our players. It's a big challenge."