Prime Minister David Cameron congratulated President Salva Kiir and the people of South Sudan on this "remarkable achievement".
Speaking after South Sudan formally seceded on 9 July, the Prime Minister said:
“Today the Republic of South Sudan becomes independent, and the world’s newest country. This is an historic day, for South Sudan and the whole of Africa. The UK is proud to have been a witness to the 2005 Comprehensive Peace Agreement and to be among the first to recognise South Sudanese independence. We welcome South Sudan into the community of nations and look forward to building ever stronger links between the UK and South Sudan in the months and years ahead.
“I have asked the Foreign Secretary to convey my congratulations to President Salva Kiir and the people of South Sudan on this remarkable achievement. Reaching this moment has required leadership and statesmanship from all sides. The actions of the government in Khartoum in recognising South Sudan’s independence have been significant, and I hope that today marks the beginning of a new and peaceful chapter in relations between North and South.”