Barack and Michelle Obama are poised to make at least $60 million (£49 million) from a book deal.

According to the Financial Times, a bidding war has started between publishers for the rights.

Although Mr and Mrs Obama will be writing separate books, they are negotiating a joint publishing deal.

A number of leading publishers are in the running. It is claimed that Penguin Random House, which has published three other books by Barack Obama, is in pole position.

These books are estimated to have earned Mr Obama $15 million over the last 11 years.

But they are understood to be facing competition from HarperCollins, Simon & Schuster, and Macmillan.

Mrs Obama made a surprise visit to a school in Washington DC on Tuesday.