No international law as far as i know.
Its CCK following other African regulators. In other countries especially outside Africa they don't start with 07 there is 03 , 08 and so on.

In Burundi they start with 76 78 (no zero!)

There was an earlier discussion on this; Kenyans would have a number like +254- XXXX - XXXX , be it mobile, land-line and so on.

On 18 March 2013 15:37, Arthur Buliva <arthurbuliva@hotmail.com> wrote:
Noted. Now I know


Date: Mon, 18 Mar 2013 13:26:27 +0300
From: tlikhanga@gmail.com

To: skunkworks@lists.my.co.ke
Subject: Re: [Skunkworks] Question on Mobile Phone Numbers

Yes, an international body (ITU-T) in conjunction with the local regulators (CCK in Kenya's case) set the guidelines.
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