[TYPO3] Creating menu based on the same level pages

[Bade Iriabho]

Hello,

root
--main1
----sub1
----sub2
------sub2.1
------sub2.2
--main2
----sub3
------sub3.1
----sub4


Given the above page scheme, I would like to create a menu that listed pages on the same level as the current page. 

So for example if you are on "main1" page, then the menu would state:

>main1
>main2

if you are on "sub1" page, then the menu would state:

>sub1
>sub2

likewise if you are on "sub2.1" page, then the menu would state:

>sub2.1
>sub2.2

B.I.