So far, Harper and the Nationals are not close to a deal and have until Aug. 16 to get one done or Harper will go back to college. The source said he expects the negotiations to heat up by Tuesday.
General manger Mike Rizzo declined to talk about the negotiations.
"I'm not going to discuss our negotiations other than to say we are in negotiations with all of our unsigned Draft choices," Rizzo said.
Harper has the stats to warrant being taken with the No. 1 overall pick. In 2008, Harper had a .599 batting average with 11 home runs and 67 RBIs in 38 games for Las Vegas High School. He followed that up with a .626 batting average, 14 home runs and 55 RBIs the next season.
Playing against a high level of competition and hitting with a wooden bat has not presented much of a challenge to Harper. The 17-year-old hit .442 with 29 home runs and 89 RBIs during the 2010 regular season. And in the National Junior College World Series, Harper hit for the cycle while going 6-for-7. The next day, he went 2-for-5 in the first game of a doubleheader and 6-for-6 with four home runs in the nightcap.