According to B3-6-05, which was updated on January 30, 2018, the answer is not necessarily.
"When a borrower has entered into an installment agreement with the IRS to repay delinquent federal income taxes, the lender may include the monthly payment amount as part of the borrower’s monthly debt obligations (in lieu of requiring payment in full) if:
The payments on a federal income tax installment agreement can be excluded from the borrower’s DTI ratio if the agreement meets the terms in Debts Paid by Others
or Installment Debt
described above. If any of the above conditions are not met, the borrower must pay off the outstanding balance due under the installment agreement with the IRS in accordance with B3-6-07, Debts Paid Off At or Prior to Closing