Regular expression to split number

I am splitting the phone number entered into two parts using regular expressions below

(^\d{3}) - last 7 digits

\d{7}\b - first 3 digits

This works fine if entered value is 1234567890 or 123-456-7890

and fails if value entered is 123 456 7890 (with spaces) or 123.456.7890

how to modify above expressions to trim (spaces and .)?

Thanks
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