While NHS trusts locally make the decisions about staffing levels, the RCN said there is a lack of national oversight about the reduction in staff numbers.
The organisation is calling on ministers to prevent NHS trusts from "continuing with this damaging agenda of cuts" that "impact on patient care".
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Julian Cadman, who is thought to have dual British-Australian nationality, became separated from his mother who was injured in the attack.
Wayne Rooney and his wife Coleen are expecting their fourth child, the couple have announced.
As the silence came to an end the crowd began to applaud and people shouted "I am not afraid!" in defiance of the attacks.