President Joe Biden will seek $80 billion to fund enhanced Internal Revenue Service enforcement of high-earners to help pay for his American Families Plan, which he is set to unveil later this week, two sources briefed on the proposal told CNN.

The administration believes the enhanced measures to crack down on tax evasion will increase revenue for the government by $700 billion, although some outside experts are skeptical and the Congressional Budget Office -- the accepted scorekeeper -- is unlikely to project that much revenue.

As CNN has reported, this is a component of how Biden plans to finance his proposal, with the tax increases on the individual side for the wealthy making up a more significant and tangible chunk.