How to publish all packages of a monorepo?

We got an `npm` monorepo with 100+ packages, the main `package.json` is set to `private`. When I run `yalc publish` I just get:
```
Will not publish package with `private: true` use --private flag to force publishing
```

and 0 packages are published (lots of packages in the monorepo are public)

How to publish all public packages? Thanks!