President Donald Trump is expected to announce he has selected the path forward for his ambitious Golden Dome missile defense shield, a U.S. official said on Tuesday.

The Congressional Budget Office estimated that just the space-based components of the Golden Dome could cost as much as $542 billion over the next 20 years.

President Donald Trump will announce $25 billion for his “Golden Dome” defense project Tuesday afternoon, according to a White House official, a fraction of the amount it would eventually cost to build the ambitious national missile system he's demanded.