"Sign for AC Milan now or the transfer from LA Galaxy is off," the Sun quoted Garber, as saying.
The 33-year-old midfielder has made it clear that he wants to call time on his two-year stint in Los Angeles to seal a permanent move to Milan.
Keeping in view, the upcoming American season that will start on March 22, Garber has set a deadline to Beckham.
"If it is not resolved by Friday, I will not approve the transfer," MLS Commissioner said.
"Milan must make an offer to buy him out of his contract that makes sense for MLS and Galaxy," he added.&13;