He said the decision not to use the MFA2 platform was due to its upcoming QX50 SUV adopting the new VC-T powertrain which cannot be incorporated into this particular platform.
"We have a very good relationship with Mercedes," said Krueger. "In this particular case, we have decided other projects needed to be prioritised [over the joint MFA2 project] and that's what we did.
"The QX50 has a unique engine so the platform needs to be for Infiniti. We have taken the decision based on brand separation."
The QX50 and Mercedes-Benz models will continue to be built alongside each other at its Aguascalientes plant in Mexico. "There are still opportunities for sharing sourcing of parts and more," Krueger said.
He added that the alliance with Daimler, Mercedes' parent company, is ongoing and that there will be other projects where the firms share platforms and parts.
On the eve of the Detroit show, Mercedes boss Dieter Zetsche confirmed that the brand is working on plans to increase its compact car line-up from five to eight models.