However, Sonnen has yet to accept the rematch with the Brazilian. The No. 1-ranked middleweight contender has denied any involvement in the main event thus far and still needs to review the contract.
"My demand has not been met," Sonnen told MMAFighting.com. "I've signed nothing."
Sonnen's manager, Mike Roberts, also confirmed that his client has yet to agree to a title bout with Silva.
Sonnen and Silva are set to meet in a rematch of their first encounter in 2010. The UFC 117 bout saw Sonnen challenge and nearly defeat the champion, as the American dominated Silva for four-and-a-half rounds before Silva's triangle choke resulted in Sonnen's submission.
Since then, Silva has successfully defended his title against Vitor Belfort and Yushin Okami, while Sonnen, after serving a one-year suspension for a failed post-fight drug test, has beaten top contenders Brian Stann and Michael Bisping.
UFC 147 is scheduled for June 23, live from the Estádio Olímpico João Havelange in Rio de Janeiro, Brazil. The venue is expected to seat approximately 80,000 fans for the event, which would surpass the UFC attendance record previously set during UFC 129 at the Rogers Centre in Toronto, which held over 54,000 fans.