How to change a request body size limit in Next JS app router_

Question

I created an API endpoint in Next JS app, using app router. It is a POST request that works as expected until the bigger body is sent.

The request is such that on different occasions it receives a different body. In some cases, body can contain one or many complex JSON objects that need to be analysed. When this is the case request responds with:

{"code":"413","message":"Request Entity Too Large"}

As a solution, I tried exporting a config object from route.ts file as below, but I cannot build my project as I get the message that it is deprecated.

export const config = {
  api: {
    bodyParser: {
      sizeLimit: '8mb',
    },
  },
};

I looked online and was not able to find any solutions yet.

Any help would be highly appreciated.