Congress appears poised to permanently prohibit the sale of tobacco to anyone under the age of 21.

The provision is expected to be included in a final year-end spending deal, according to a senior Democratic aide.

The provision, which is supported by many major public health groups, was included as part of a bipartisan and bicameral legislative package to fix surprise medical bills. But turf wars and partisanship have derailed that legislation and lawmakers wanted to ensure the tobacco provision survived intact.

The tobacco legislation was originally sponsored by Sen. Tim Kaine (D-Va.) and Senate Majority Leader Mitch McConnell (R-Ky.), and has broad, bipartisan support from Sens. Brian Schatz (D-Hawaii), Todd Young (R-Ind.), Dick Durbin (D-Ill.) and Mitt Romney (R-Utah).

While larger efforts to regulate tobacco by banning certain flavors and e-cigarettes have stalled at the federal level, lawmakers believe raising the tobacco purchasing age will make a difference.

Tobacco companies are on the front line pushing for the legislation at the federal and state levels, mainly in an effort to stave off stronger regulations that could have disastrous effects on the industry.

Industry giant Altria has endorsed the bipartisan legislation. Public health groups have said any tobacco industry support makes them wary, but they have praised the effort.