How to have multiple purchase order approval limit for GM

HI

Good Evening,

We are using R12.1.3

For purchase order approval we are using standard PO approval  POSITION HIERARCHY. We  set limit for GM 50000 and is working fine.

Now we have below requirement.

• For any PO related  to  project purchase the GM will have limit of 50000.
• For any PO related to Office Administration the GM will have limit of 1000.

Can you please suggest a way to meet this requirement

Thanks

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