Defence Minister Jess Phillips resigned from Prime Minister Keir Starmer's government on Tuesday, saying "actions, not words, matter."
Phillips has become the second minister in Starmer's cabinet to resign.
Earlier on Tuesday, this was done by the minister, Miatta Fahnbulleh.
Prime Minister Starmer has come under increasing pressure to resign, following the Labour Party's heavy losses in last week's local elections.
However, Starmer is currently refusing to do so.