Get compile error "Could not find a declaration file" importing Ionic Pro with strict checking

I am importing ionic/pro in my app:

import { Pro } from '@ionic/pro';

It all builds and runs fine. But when I enable the strict compiler option in my tsconfig.json, with the "strict": true compiler option, I get an error:

Could not find a declaration file for module '@ionic/pro'. '<path_to_my_app>/node_modules/@ionic/pro/dist/ionic-pro.module.min.js' implicitly has an 'any' type.
  Try `npm install @types/@ionic/pro` if it exists or add a new declaration (.d.ts) file containing `declare module '@ionic/pro';`

Is there a workaround or fix for this?


cli packages: (.........\AppData\Roaming\npm\node_modules)

    @ionic/cli-utils  : 1.19.1
    ionic (Ionic CLI) : 3.19.1

global packages:

    cordova (Cordova CLI) : 7.1.0

local packages:

    @ionic/app-scripts : 3.1.6
    Cordova Platforms  : android 6.3.0
    Ionic Framework    : ionic-angular 3.9.2


    Android SDK Tools : 26.1.1
    Node              : v8.9.3
    npm               : 5.6.0
    OS                : Windows 8.1

Environment Variables:

    ANDROID_HOME : C:\Android


    backend : pro