Problems with logout in ionic

Ionic Framework ionic-v3
1

I am new to ionic app development. I have Implemented the login and logout logic like below.

Login in login.ts

loginUser(){
    if (!this.loginForm.valid){
      console.log(this.loginForm.value);
    } else {
      this.authData.loginUser(this.loginForm.value.email, this.loginForm.value.password)
      .then( authData => {
        this.navCtrl.setRoot(TabsPage);
      }, error => {
        this.loading.dismiss().then( () => {
          let alert = this.alertCtrl.create({
            message: error.message,
            buttons: [
              {
                text: "Ok",
                role: 'cancel'
              }
            ]
          });
          alert.present();
        });
      });

      this.loading = this.loadingCtrl.create({
        dismissOnPageChange: true,
      });
      this.loading.present();
    }
  }

Logout in home.ts

logout(){
     this.authData.logoutUser()
    .then((user) => {
      let alert = this.alertCtrl.create({
        message: "You are logging out",
        buttons: [
          {
            text: "Ok",
            role: 'cancel',
            handler: () => {
              this.navCtrl.setRoot(LoginPage); 
              this.navCtrl.popToRoot();                  
            }
          }
        ]
      });
      alert.present();
    }, (error) => {
      var errorMessage: string = error.message;
      let errorAlert = this.alertCtrl.create({
        message: errorMessage,
        buttons: [
          {
            text: "Ok",
            role: 'cancel'
          }
        ]
      });
      errorAlert.present();
    });
  }

The firebase authentication works properly. The issue here is when logging in I am setting the TabsPage as the root. 
Then in logout 

      this.navCtrl.setRoot(LoginPage); 
          this.navCtrl.popToRoot();  

**After logout the login page appears and the tabs are also appearing in the LoginPage. How can I solve this?**