The US Attorney General Eric Holder has said that authorities negotiated with BP to resolve the civil claims it is facing but was unable to reach a "satisfactory" number.
He added that is was possible that the US and the oil giant could still resolve the claims out of court, but that officials are preparing for trial.
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Warm with some wet weather
Melissa Mead has been campaigning to raise awareness of sepsis after losing her one-year-old son William to the illness.
Last year, spring was colder than winter, with snow at the end of April for the first time since the mid 1980s.