Access internally stored object used for class delegation

When using Class Delegation, is there a way to access the internally stored object without providing it in the primary constructor and storing it in a property?

interface Base {
    fun a()
}

class BaseImpl : Base {
    override fun a() {}
    fun b() {}
}

class Derived : Base by BaseImpl() {
    fun c() {
        // Is there a way to call b() here?
    }
}

I know this is a possibility:

interface Base {
    fun a()
}

class BaseImpl : Base {
    override fun a() {}
    fun b() {}
}

class Derived private constructor(private val base: BaseImpl) : Base by base {

    constructor() : this(BaseImpl())
    fun c() {
        base.b()
    }
}

But it would be nice if the internally stored object, used for forwarding the Base-methods to, was available without needing to store it explicitly.

No, there is no other way to access the object.