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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Fine this evening, then dry overnight with mist likely in places. Sunny spells tomorrow morning with hazy sunshine in the afternoon
A fine and sunny evening, then dry and clear overnight. A sunny start to Monday with hazy sunshine into the afternoon and feeling fresher
The grass pollen risk will rise to very high during warm, sunny weather. Weed pollen will also be airborne