A change of plan has led to the death of an Australian nanny in the London terror attack.

21-year-old Sara Zelenak, who is from Brisbane, had been missing for several days but it's now been confirmed she lost her life in the attack.

Australia Correspondent Donna Demaio told Rachel Smalley she had planned to stay home and babysit.

"At the last minute, the grandmother of the child said 'no, no, you go out with your friend, and that's why she was on London Bridge."

Another Australian woman, nurse Kirsty Boden, also died in the attack as she tried to help injured people.

LISTEN TO DONNA DEMAIO SPEAK WITH RACHEL SMALLEY ABOVE