Simple If statement throws an error

My IF statement returns an error. I am guessing I have an End IF, or Else in the wrong place...

Sub OpenNewSheet()

    Dim ans
    Dim ws As Worksheet
    
    If Left(ws.Name, 5) = "Sheet" And Left(ws.Name, 6) <> "Sheet1" And Left(ws.Name, 6) <> _
    "Sheet2" And Left(ws.Name, 6) <> "Sheet3" And Left(ws.Name, 6) <> "Sheet4" Then
    ws.Delete
    Else
       ans = MsgBox("Do you want to view this sheet?", vbYesNo)
                If ans = vbYes Then
                    End
                Else
                    ActiveSheet.Delete
                End If
    End If

End Sub

Thanks

Ronan