LONDON (Reuters) -Britain's Queen Elizabeth spoke with Prime Minister Boris Johnson by phone on Wednesday as she continued to carry out official duties days after testing positive for COVID-19, a Buckingham Palace spokesman said.

       Buckingham Palace said on Sunday that Elizabeth, 95, was suffering mild cold-like symptoms but was expected to carry on with light engagements, suggesting the world's current oldest and longest-reigning monarch was not seriously unwell.

       She spoke to Johnson as part of her weekly conversation with the prime minister.

       The queen, who has been fully vaccinated against coronavirus, joked last week that she could not move much and fears about her health have mounted since she spent a night in hospital last October for an unspecified ailment.

       (Reporting by Andrew MacAskillEditing by Chris Reese and Aurora Ellis)