Conservative bishops in the Anglican Church of Canada have condemned the vote to allow same-sex marriage in as a "fundamental departure" from the Church's teaching.

In a statement, the seven bishops warn of serious "complications" in relations with the Anglican Communion as a result.

Hinting at the possibility of future division, they say the vote "imperils" their own relationship with the Anglican Church of Canada. 

They criticise the process, which began in 2013 and which this week featured a wrong vote count that led to the initial "result" in General Synod being reversed, as "flawed".

Before the change becomes law, it has to go through a second reading at the next synod in 2019.

The bishops say the vote has "inflicted terrible hurt and damage".

Some bishops have have said they will go ahead with same-sex marriages immediately and not wait for 2019.

The conservative bishops warn that the vote "imperils" their full communion within the Anglican Church of Canada and with Anglicans throughout the world.

"We believe that our General Synod has erred grievously and we publicly dissent from this decision," they state, condemning it as "a fundamental departure from the faith and teaching held by the majority of the Anglican Communion on the doctrine of marriage."

They also criticise all expressions of homophobia.