LOS ANGELES -- MLS intends to expand to 30 teams, with teams 28 and 29 requiring an expansion fee of $200 million, commissioner Don Garber announced Thursday following a Board of Governors meeting.

Garber said the board had authorized his office to advance into exclusive discussions with St. Louis and Sacramento with an eye toward those two cities being the 28th and 29th teams.

MLS currently has 24 teams and has already confirmed expansion teams in Austin, Miami, and Nashville to join in the coming years.

"In the last 10 years we've been experiencing unprecedented growth for a major league in North America," Garber said. "Expansion has been a key driver of that growth and it really is a great measure of the enormous enthusiasm and the commitment that our fans have in markets both new and old to support our league and our players and to see the sport grow."

Garber said the ownership groups from both cities will make formal presentations to the league's expansion committee in the coming weeks. Part of the process will involve getting to know the respective ownership groups, both of which have investors who are relatively new to the process. Garber hopes a final decision on both cities would be made before this summer's All-Star Game in Orlando in late July.

"We'll be asking them for their formal and final plans for a commitment of corporate support, the final composition of their ownership group, and detailed economics on their funding of both their team operations and their stadium plans," said Garber.

While the league has said at times that it would stop expanding at 28 teams, the announcement was not a surprise. Garber said the strength of the Sacramento and St. Louis bids was part of what drove the Board to decide to expand to 30 teams.

Sacramento's hopes of landing a team were boosted in January when billionaire Ron Burkle became the new lead investor in the Sacramento Republic soccer team. The team currently plays in the second-tier United Soccer League.

Burkle is a co-owner of the NHL's Pittsburgh Penguins with a net worth estimated at $2 billion by Forbes magazine.

The St. Louis group includes World Wide Technology CEO Jim Kavanaugh and the Taylor family, owners of the rental car company Enterprise Holdings.

In a statement released on Thursday, the Sacramento Republic said: "Today is a monumental step in the process and we are closer than ever to reaching our goal of bringing Major League Soccer to Sacramento. There isn't a better fit for MLS than our city and today's announcement is a testament to the strength of Sacramento's bid, and most importantly, to the faith and devotion of Republic FC fans. We will continue our ongoing communication with the Commissioner and with MLS and look forward to finalizing all next steps to deliver MLS to Sacramento."

In terms of what number of teams the league will stop expanding, Garber didn't commit to a definitive number.

"I don't know that we have a firm handle yet on what the final number of teams in the league ought to be," said Garber. "We have a lot of work to do to determine what the future state of MLS is in 10 years and in 20 years. We continue to believe that there are many, many cities across the country that could support an MLS team, with a great stadium and a great fanbase and great local ownership that will invest in the sport in their community."

Garber added that MLS will "take our time" on team 30, though it remains in discussions with the likes of Phoenix, Las Vegas, Detroit and Charlotte.

"We don't want to be unbalanced, but at the same time I think we do need to take a bit of a deep breath and on-board the teams that are going to be coming in over the next number of years."

Garber lauded the bids of Sacramento and St. Louis but also stressed that both ownership group still had work to do. Garber said that Sacramento needed to finalize their corporate sponsorship as well as some elements of the stadium plan. St. Louis needs to finalize its stadium plan as well, but Garber's expectation is that both cities will get their respective bids over the line.

"I've got confidence in both markets," said Garber. "We wouldn't be here today without the confidence of our ownership group to try to put all the elements in place to give them the opportunity to finalize the deal."

Information from The Associated Press was used in this report.