1
general::
Phrase(s): lead up to something
1. Lit. to aim at or route movement to something. • A narrow path led up to the door of the cottage. • This road leads up to the house at the top of the hill. 2. Fig. to prepare to say something; to lay the groundwork for making a point. (Typically with the present participle.) • I was just leading up to telling you what happened when you interrupted. • I knew she was leading up to something, the way she was talking.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Prepare gradually for, result in gradually, as in These events clearly led up to the coup, or His remarks led up to the main point of the speech, that he was going to resign next year. [Mid-1800s]
American Heritage Idioms