Regex (or formula) to parse then replace with

Hi All,

I have a column that contains numbers such B1001 B12345 B01234534 (so it always starts with a B). I'm using regex to parse the number section ^B0?(.+)$, so B1001 becomes 1001 B01234534 becomes 1234534 (ignoring leading zeros). 

The challenge is to append "AS TE" to the parsed number so 1001 becomes AS TE 1001 or 1234534 becomes AS TE 1234534. Can i do that with a SINGLE regex or formula function (I know that I can use multiple regex functions to achieve the result that I desire, but I'm curious whether I can do with a single function

Thanks