Sudan's president says unless weeks of border fighting with South Sudan is resolved there will be no talks on oil or trade.<br /><br />Tension has been high since South Sudan gained independence from Sudan last July. <br /><br />South Sudan inherited the majority of the region's oil fields in the split. <br /><br />Sudan's oil revenue has fallen this year by $2.2bn. <br /><br />As Mohamed Vall explains, it's one of the reasons why Khartoum is facing an economic crisis.
