import re

def remove_disclaimer(text):
    # The pattern matches the start and end of your phrase.
    # \s+ matches one or more spaces/newlines/tabs.
    # re.IGNORECASE makes it case insensitive just in case.
    
    pattern = r"Caution:\s+This\s+email\s+comes\s+from\s+an\s+external\s+sender.*?\s+contact\s+your\s+IT\s+Department\.?"
    
    # Substitute the found pattern with an empty string
    cleaned_text = re.sub(pattern, "", text, flags=re.IGNORECASE | re.DOTALL)
    
    return cleaned_text.strip()