In a statement released earlier this week, Reform said that Orthodox Anglicans 'had been in effect excluded' as a result of the changes.
Reform council chairman, Preb Rod Thomas, said: "It is difficult to see how the process of shared conversations can command credibility if those who are most committed to the Church of England's official teaching are in effect excluded."
However, Church officials have responded, saying: "The objectives of the Shared Conversations on Sexuality, Scripture and Mission were set out in June 2014 by the Bishop of Sheffield in GS Misc 1083.
"These objectives remain unchanged. No new objective has been added."
The Church is currently undergoing a process of finding out the best way to respond to the issue of sexuality in today's society.
It offered strong opposition to the Marriage (Same Sex Couples) Act 2013 and has since banned any clergy from marrying same-sex partners.