Controversial changes to sections six and seven of the Act, which set out environmental bottom lines, have been "pulled back".
The only change in these sections would be to the management of risks from natural hazards.
Dr Smith said the Maori Party had agreed to back the legislation to a select committee.
He described it as a "compromise bill" because of the environmental concessions, which had "changed the tone" of sections six and seven.
In the original reforms, the Government had proposed giving equal weight to economic development and environmental protection in planning decisions.
This was the Maori Party's primary concern about the legislation, and this section had amended to secure their support.
Further concessions had also been made to the Maori Party.
These included the removal of a requirement for iwi farmers to get resource consent for taking stock water from rivers. At present, this provision only applied to individual farmers and not farms which were owned by companies or incorporated societies