The invitation was said to be at the instance of an activist, Kayode Bello, who petitioned the House over the matter.
Some of the non-refundable fees paid by most applicant include application fees, evaluation fees, courier fees, service fees, visa fees, school fees.
While some of the students claimed that they were denied visas because they were not married, others said they were denied because only one of their parents was their sponsor.
A parent claimed that his daughter’s interview was cut short because she asked the interviewer to speak up.
Our correspondent was further told that the embassy usually issued preprinted blue papers to those it rejected without giving a specific reason for the decision.
A former ambassador to the US, John Campbell had, however, told our correspondent visas were given by consular officers on a case by case basis, adding that the refusal of many people to return home after finishing their programmes made the process difficult.
The activist, Bello, petitioned the National Assembly through member representing the Ede and Ejigbo Federal Constituency, Prof. Mojeed Alabi, after suffering a similar fate of denial.
The summon, entitled, ‘Indiscriminate denial of United States of America visa and illegal increment of exchange rate of visa fee by the American embassy’ was signed by the House Committee Chairman on Public Petitions, Uzo Azubuike.
The two-page document, dated November 27, 2018 and a copy of which was received by our correspondent, said the hearing would hold on Tuesday, December 4 at 2pm at the House of Representatives Room 429.
The House asked the ambassador to present 20 copies of his defence.
The Clerk of the House, Mr Omale Adoyi, confirmed the development to our correspondent on Monday.
He, however, said the US embassy rejected the summon.
“But we will go on with the hearing and may have to adjourn if they fail to show up,” he added.