Prime Minister Gordon Brown's spokesman Michael Ellam said Miliband would discuss the charge of inciting religious hatred against teacher Gillian Gibbons. The meeting with Ambassador Omer Mohammed Ahmed Siddig will take place as soon as possible, the Foreign Office said.
"We are surprised and disappointed by this development and the foreign secretary will summon as a matter of urgency the Sudanese ambassador to discuss the matter further," Ellam said.
He said Miliband would ask "for the rationale behind the charges and a sense of what the next steps might be" amid an escalating diplomatic dispute in the case.
"We will consider our response in the light of that," Ellam said.