Ionic 3 - Unable to click on alert dialog shown above google maps

I am implementing a alert dialog using AlertController in ionic 3 as follow

let alert = this.alertCtrl.create({
 title: 'Low battery',
 subTitle: '10% of battery remaining',
 buttons: ['Dismiss']
});
alert.present();

This alert dialog is visible above google maps, but I am unable click on this alert button, any click on alert dialog is still treated as I am clicking on google maps below it. Even with alert dialog shown above the map I am still able to interact with the map as usual, I can click any marker in map, I can zoom in, zoom out.