Joe Biden will not shy away from using U.S. President Donald Trump's weapon of choice — sanctions — as he seeks to reshape America's foreign policy, according to people familiar with his thinking.

But when Biden takes office on Jan. 20, he is expected to quickly begin recalibrating Trump's blunt-force approach while taking time to deliberate before making any major changes with top sanctions targets like Iran and China, the sources said.

His challenge will be to sort out which sanctions to keep, which to undo and which to expand. This will come after four years in which Trump has imposed punitive economic measures at a record pace — often unilaterally — but has failed to bend U.S. rivals to his will.