The widow of Russian ­dissident Alexander Litvinenko, who died after being poisoned in London, has "courageously" decided to fight on to force a public inquiry.

Last week Marina Litvinenko broke down in tears as she said she was struggling to fund her battle against the UK Government's decision to await the outcome of a normal inquest before deciding whether there should be a wider-­ranging inquiry.

Mrs Litvinenko says she wants to uncover the truth of how her husband, a former KGB spy, died seven years ago.

She appealed to the ­British public for money to finance her case after High Court judges refused last Thursday to protect her against a potentially ruinous costs bill of up to £40,000 if she loses.

Her solicitor Elena Tsirlina said: "Mrs Litvinenko has made a courageous decision to pursue her judicial review claim against the Home Secretary's decision not to hold a public inquiry and to continue her fight to uncover the truth about her husband's death, despite mounting adversity."

Mrs Litvinenko wants the High Court in London to rule that Home Secretary Theresa May was wrong not to order a public inquiry into her 43-year-old husband's death in 2006.

The High Court will now have to decide whether she has an arguable case which should go to a full hearing.