Could you please let me know the difference between "Do the needful" and "Please do the needful". Does it have same weightage in terms of respect. "Do the needful" is a respecful statement ?
Welcome, Bhaskar J.
"Do the needful" is a phrase which means "do that which is necessary", and carries the respectful implication that you trust the other party to understand what needs doing without being given detailed instruction. It is commonly used in India and widely attributed as an Indianism, but the phrase may have its origins in British English instead, according to the Universal Dictionary of the English Language of 1932.
Source: Do the needful: Information from Answers.com
Adding please makes it sound more polite. Note that, it's not a common phrase in North American.
All the best.