At this stage, Urtubey looks likely to face dissident Peronist leader Sergio Massa in a primary, with the winner then leading a Peronist ticket through the general and presidential elections in late October.
"Argentina is unviable with a 800-point country risk", Urtubey charged.
"I don't foresee a default. Argentina cannot allow another default, it would be mortal. We must get it out of our heads that the solution is to not comply (with the loan terms)", he said.
As a presidential hopeful, the Salta leader is proposing major institutional changes like the appointment by Congress of the national Executive's Cabinet Chief, or "a semi-parliamentary system" as he described it.
He also said he would commit to "carrying out more consultation, and in a permanent way, with the people on key issues and decision making".
"Argentina Federal invites all sectors of society, it is broader than just Peronism", he said of his electoral pact with Massa, Peronist Senate minority leader Miguel Angel Pichetto and the Governor of Cordoba province Juan Schiaretti.