(a)
General rule
If the taxpayer files a petition with the Tax Court, the entire amount redetermined as the deficiency by the decision of the Tax Court which has become final shall be assessed and shall be paid upon notice and demand from the Secretary. No part of the amount determined as a deficiency by the Secretary but disallowed as such by the decision of the Tax Court which has become final shall be assessed or be collected by levy or by proceeding in court with or without assessment.