SAML sender-vouches or ECP for REST web services?

Hi Experts.

We use SAML in the environment with an SAP IdP. This works for some scenarios.

I am struggling with this:

We have an ABAP system (A) with a REST service (in SICF). A user (U) accesses some application on a 3rd party system (N) that in turn needs to access the SAP REST service to get some data from the SAP system, and this call should be performed in the context of the end user.

So U->N->A.

The user should be authenticated in A using SAML, and I found several profiles that could work: holder of key, sender-vouches, enhanced client proxy (ECP).

But both the documentation and the actual configuration options in the system look like these profiles only work for SOAP services(?), like you need to do things in the SOAMANAGER for example.

Are SAML profiles like sender-vouches etc. supported for REST services (in SICF)?

Best regards

Jens