The Church of Scotland is expected to decide whether to allow its ministers to be in same-sex marriages at its annual General Assembly.

The assembly, which opens in Edinburgh on Saturday, is to vote on extending a law passed last May that permits ministers to be in same-sex civil partnerships.

Presbyteries were sent the issue of also allowing same-sex marriage ministers for further discussion at last year's event, deferring a decision on the matter until this year.

In 2015 the assembly was told that the measure would not change the Church's traditional stance on marriage, or amount to a recognition of the validity of same-sex marriage.

The outcome of last year's vote on civil partnerships followed years of deliberation within the Church.

As a result of the decision, the Kirk adopted a position which maintains a traditional view of marriage between a man and woman, but allows individual congregations to "opt out" if they wish to appoint a minister or a deacon in a civil partnership.

But because that debate pre-dated the legalisation of gay marriage, the change related only to civil partnerships, not same-sex marriages.