Amazon founder Jeff Bezos has branched into publishing by buying newspaper The Washington Post for $250m.

Bezos has used his personal fortune to snap up the newspaper which will operate separately from Amazon. He will become the sole owner of the newspaper when the sale completes.

Bezos, whose personal net worth is estimated at more than $25bn according to Forbes magazine, has not detailed his plans for the publication.

However, in a letter to employees, he said: “There will, of course, be change at The Post over the coming years. That’s essential and would have happened with or without new ownership. The Internet is transforming almost every element of the news business: shortening news cycles, eroding long-reliable revenue sources and enabling new kinds of competition, some of which bear little or no news-gathering costs.

“There is no map, and charting a path ahead will not be easy. We will need to invent, which means we will need to experiment. I’m excited and optimistic about the opportunity for invention.”

The Washington Post Co chairman and chief executive Donald Graham said: “Jeff Bezos’ proven technology and business genius, his long-term approach and his personal decency make him a uniquely good new owner.”