When the British under Herbert Kitchener moved into the Sudan in 1898, the Khalifa sent a force under Emir Mahmud Ahmad to join with Osman's army. Osman's plan to outflank Kitchener by moving up to Atbara was approved by the Khalifa, but Mahmud overruled Osman, when he proposed to move their forces even further upriver to Adaramra, threatening Kitchener's line of communications. Instead Mahmoud created a fortified defensive camp at Atbara.
In 1898, British troops led by Herbert Kitchener invaded the Sudan. The Khalifa sent Emir Mahmud Ahmad and his army to join Osman's forces. Osman planned to outflank Kitchener by moving towards Atbara, which was approved by the Khalifa. However, Mahmud overruled Osman's plan and suggested a move further upriver to Adaramra, threatening Kitchener's supply lines.  Mahmud then established a fortified camp at Atbara to defend against Kitchener.