Barclays said it will contest a record £300 million fine imposed by the US energy regulator in court.
The Federal Energy Regulatory Commission has accused the banking giant of fixing electricity prices in California and other states for more than two years.
Four of Barclays former traders also received fines for allegedly fixing power prices between November 2006 and December 2008.
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Top temperature 14 Celsius (57 F).
The Prime Minister will say Moscow's brazen flouting of international law represents a threat to the basis of democracy across Europe.
In some cases, victims of violence and other serious crimes face long delays as forces are unable to dispatch officers promptly.