Work on the new Corinthians stadium in Brazil's largest city, which has not started yet, is highly unlikely to be finished in time for a tournament widely regarded as a dress rehearsal for the 2014 finals, Silva said.
"The works plan for the Sao Paulo stadium requires 33 months so evidently that plan drawn up by the (Sao Paulo) state government, prefecture and Corinthians, owners of the stadium, doesn't contemplate the Confederations Cup," he told reporters.
"It looks like it will be very difficult for Sao Paulo (city) to participate (in the tournament)," Silva added.
Pele, who has been critical of the progress made in getting Brazil ready to host world soccer's showpiece event in 2014, has been approached to be a consultant to the local organising committee, the minister said.
The increased capacity is necessary to meet FIFA stipulations for staging the World Cup's opening match but the delays are clearly exasperating Silva.
"It's been some time since I've been told that it will be in the next few days and I hope the next days really are next," Silva said.
FIFA president Sepp Blatter criticised Brazil's delays in March, citing Sao Paulo as a particular worry given plans to use it during the 2013 event.
FIFA's general secretary Jerome Valcke was in Brasilia last week for talks with Brazilian authorities about progress on preparations for 2014.
Silva said Valcke was worried about Brazil's inadequate airports but satisfied with the government's measures to deal with the problem.
He said President Dilma Rousseff would meet officials of the 12 venue cities and states on May 30 and "alert them about deadlines". He added she would announce measures for airports and urban transport.
"Pele is a symbol of Brazil, of Brazilian football, of a victorious Brazil," he said. "We want Pele not only as an ambassador but a consultant. He knows how the world views us and we want to improve how the world sees us."
