The deal for the Georgetown site, which includes 3000 and 3050 K St. NW, is set to close by the end of the month, sources say.
MRP and Prudential declined to comment.
Prudential paid $220 million for the waterfront property in 2004, according to land records, and put the property on the market in March.
The property has changed hands several times over the past decade or so, selling to Crescent Real Estate Equities in 1998 for about $305 a square foot, then to San Francisco-based Shorenstein in 2001 and to Prudential in 2004. Shorenstein paid $154.25 million, or $287 a square foot.
A $240 million price tag would come out to about $446 per square foot.