Which part of the Indian Constitution, although non-justiciable by courts, is explicitly declared to be fundamental in the governance of the nation?

Explanation

Under Article 37 of the Indian Constitution, it is clearly stated that the provisions contained in Part IV (Directive Principles of State Policy) shall not be enforceable by any court. However, these principles are fundamental in the governance of the country, and it is the duty of the State to apply them when making laws.