Sudan's Prime Minister Abdalla Hamdok will probably come away empty-handed from his first trip to Washington DC since replacing the overthrown Omer el Beshir as Sudan's leader. Top of Hamdok's wish-list is that the United States end its economic sanctions against Sudan and remove its designation as a 'state sponsor of terrorism', which has been in place since 1993.

In an open letter to President Donald Trump, Sudanese intellectuals, politicians, business and civil society leaders compared the designation to 'using a sledgehammer to crack a nut'.

US officials have been gently encouraging thus far, but without giving any clear commitments. 'It's not flipping a light switch. It's a process,' Tibor Nagy, the administration's most senior Africa official, said last month. Nor is it something that the Trump administration can deliver by executive fiat; Congress would need to agree.

Yet patience is not a luxury that Hamdok's government can afford, and that explains why Hamdok has taken a tougher line, warning that without lifting sanctions his government risks collapsing, and Sudan breaking into multiple regional caliphates.

The designation makes Sudan a pariah state economically, as well as politically, ineligible for debt relief and financing from the IMF and World Bank. Hamdok will survive in short term but if the sanctions stay they will hold back his reforms and, perversely, strengthen the hands of the military.