How to create a link to external URL in Angular 2

I am new to Angular. I am starting with ver. 2.
I need to link to a file://... URL. I tried normal href:

Note: app is a model object of the web which deals with applications.

<a target="_blank" href="file://{{app.outputPath}}/index.html">no link here</a>.

That doesn't work - the link is there, with correct URL, but Angular seems to block the event somehow. Why?

So I've seen ng-href but that's for Angular 1.x. And there's no *ngHref from what I can tell. So this was just a naive try:

<a target="_blank" *ngHref="file://{{app.outputPath}}/index.html">over a directive</a>.

Also I have seen something with routing but that appears to be intended only for internal links within the application:

<a [router-link]="['/staticReport', {path: app.outputPath}]">see the report</a>.

app.component.ts:

@RouteConfig([
    ...
    {path:"/staticReport/:path", redirectTo: 'file://  ???? ' }
])

What's the way to create an external link?