Dr Rowan Williams is due to speak as the Church's national assembly gathers after the legislation failed to gain the necessary two thirds majority amongst lay members.
His statement will come after an emergency meeting of the Church of England bishops following the narrow defeat.
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Cloudy and breezy for much of the day. Rain and stronger winds arriving tonight.
A mostly dry but cloudy morning. Heavy rain and stronger winds this evening.
Another cloudy and breezy day tomorrow. Turning windy with rain arriving tomorrow evening.