Is it possible to communicate directly between 2 APIGateways in the same account?

I created a first APIGateway A (sub1.custom-domain.com) with a couple of apis and I have another APIGateway B (sub2.custom-domain.com) within the same account. I have an API /items in ApiGateway A that requires to call another API /providers that is located in the ApiGateway B. I tried to add a role to the lambda function items_lambda to invoke the ApiGateway B but it returns an error 403 Forbidden.

That's the policy I added in order to invoke the apis from ApiGateway B but it does not fix the issue.

{
       Version = "2012-10-17"
       Statement = [{
          Action = "execute-api:Invoke",
          Effect =  "Allow",
          Resource = "arn:aws:execute-api:${region}:*:*/*"
    }]}

Does the policy wrong or should I make the called resource more specific to access the exact path?