The first thing the project manager should do is to evaluate the impact that the inclusion of this new requirement will have on project performance. This is because the project manager needs to assess how the new requirement will affect the project scope, schedule, cost, quality, risk, and stakeholder satisfaction. The project manager should also consider the feasibility, desirability, and viability of the new requirement, and whether it aligns with the project objectives and business case. Based on the impact analysis, the project manager can then decide whether to accept or reject the change request, or to escalate it to the appropriate authority for approval. The project manager should also communicate the results of the impact analysis to the stakeholder and explain the rationale behind the decision. References:

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