The Laws of Prayer (The morning services) (49)

1. When in the middle of the Amidah, one is not allowed to interrupt by moving from one’s place. However, during the supplications at the end of the prayer, (e.g. during Elokai Netzor) one may uproot one’s feet for things which have a relevance to a Mitzvah. (Shulchan Aruch and Mishne Berurah 104)

2. Interruption with speech is worse than interruption with walking. It follows that if a person is praying the Amidah and something comes which is putting him in danger (e.g. an animal or car etc.), it is better that he should walk to another place rather than interrupting by speaking. (ibid)