A Fitch Ratings statement said its placement of the UK on a negative watch indicated a "heightened probability of a downgrade in the near term."
The RWN reflect the latest economic and fiscal forecasts published by the Office for Budget Responsibility (OBR) that indicate that UK government debt will peak later and at a higher level than previously expected by Fitch.
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A remarkably mild night with misty low cloud on the hills of Scotland, Wales and north-west England and further rain in places.