Speaking in Thunder Bay this morning, Horwath would say only there is "ample room" in her plan to develop the massive chromite deposit without delay.
A spokeswoman for the NDP says the Ring of Fire work is covered under the party's $29-billion infrastructure commitment, which mirrors the plan in the Liberal budget.
Horwath is scheduled to face off against Premier Kathleen Wynne in a debate on northern issues just after noon.
Progressive Conservative Leader Tim Hudak refused to take part in the debate, citing a scheduling conflict, and instead made a campaign stop in Peterborough today.
Wynne has pledged to spend $1 billion to build a transportation route to the remote Ring of Fire deposit, with or without Ottawa's help, if the Liberals are re-elected.
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