MLS Commissioner Don Garber discussed the issue during a chat with reporters at halftime of the Toronto-Montreal Amway Canadian Championship on Wednesday night, the website said.
"We are deeply engaged with potential ownership groups and we're hopeful to be able to announce a 20th team [for the soccer league] within the next [four to six weeks]," Garber said, in comments first reported by the Associated Press.
Referring to negotiations with the city, Garber added, "We're making progress."
"We continue — you've heard this for the last year — but we continue to negotiate with the City of New York and meet with local political folks and community leaders to get support for the stadium we hope to build in Flushing Meadows Park," Garber said.
League officials hope to open the $300 million stadium by 2016 and are negotiating with the Mets to use the parking lot at Citi Field.
The MLS has yet to find a replacement for the parkland that it is planning to use, which is necessary for the project to move forward.
"MLS continues to talk to park users, community leaders and the city about options for replacement parkland," league spokeswoman Risa Heller said in an email.