A United Methodist Church (UMC) pastor in the United States had had a formal complaint filed against him by a same-sex couple who are part of his congregation because he refused to officiate at their wedding.

Kenneth Barner and Scott Chappell have charged Rev Kelly Carpenter, pastor of Green Street church in Winston-Salem, North Carolina, with "failure to perform the work of ministry", according to the United Methodist News Service (UMNS). They also accuse him of "gender discrimination".

Both are chargeable offences according to the UMC's Book of Discipline. However, so is officiating at a same-sex wedding.

According to Barner and Chappell, the rules are contradictory. "God's grace is available to all and so should the pastoral ministry (be)", the charge says.

Carpenter is sympathetic to the cause, saying: "If there was a way for me to be a co-signer with the complaint, I think it's right on the money.

"It really calls out the contradictions in our Book of Discipline, which calls us to be ministry with all people."

The church had made its stance on same-sex weddings clear in March 2013, when its leadership council decided not to hold any weddings at all in the church sanctuary until the denomination lifted its ban on same-sex marriage.

The UMC allows pastors to perform a service of relationship blessing which must not include vows, the exchange of rings or a pronouncement of marriage.

Carpenter offered this service for Barner and Chappell, but they declined, asking him to perform their wedding off-site from the church; Carpenter was obliged to refuse and the couple filed the complaint.

Chappell told UMNS: "It's the same reason why we didn't leave the state when other states had marriage equality. It felt like having to go elsewhere or having an altered ceremony in order to comply with United Methodist rules seemed diminished in some way. We declined to do that and chose to this instead so we can start this conversation."

Carpenter said: "This may get me in some trouble, but it may be the kind of trouble I've been looking for."

Same-sex marriage has been legal in North Carolina since October.