Mr Ningi has threatened to sue the Senate if his 12 March suspension is not reversed within seven days.
Suspended Bauchi Central senator, Abdul Ningi, has written to the Senate President, Godswill Akpabio, demanding his reinstatement.
Mr Ningi conveyed the letter through his lawyer, Femi Falana, a Senior Advocate of Nigeria (SAN).
According to the letter, Mr Ningi gave a seven-day ultimatum to the senate leadership to reinstate him or risk legal action.
The Senate suspended Mr Ningi for three months on 12 March, for accusing the leadership of the Senate of fraudulently smuggling projects worth N3 trillion into the 2024 budget.
The lawmaker had claimed that he sought the services of a private auditor to review the budget and discovered some projects that did not have locations.
PREMIUM TIMES has reviewed the claims of Mr Ningi and found them to be true.
This newspaper reviewed the proposed 2024 budget, the approved budget and Mr Ningi's document which he uses as a reference and discovered several projects worth billions of naira without specific locations and a proper description.
My suspension illegal
In the letter addressed to the Senate leadership, Mr Ningi maintained that his suspension was illegal because the Nigerian parliament does not possess the power to "suspend or expel a legislator and confiscate his salaries and allowances."
The senator said he would not hesitate to report Mr Akpabio to the Legal Practitioners Disciplinary Committee if the Senate leadership refused to lift his suspension within seven days.
The upper legislative chamber is currently on Easter and Eid-el-Fitri holiday and will reconvene on 16 April.
The letter reads: "On March 9, 2024, our client granted an interview to the BBC Hausa Service on the 2024 Appropriation Act. He expressed his views on the budget of the Federal Government in the exercise of his fundamental right to freedom of speech guaranteed by Section 39 of the Constitution of the Federal Republic of Nigeria, 1999 (as amended) and Article 9 of the African Charter on Human and Peoples Rights (Ratification and Enforcement) Act (Cap A9) Laws of the Federation of Nigeria, 2004.
"Dissatisfied with the interview, you caused our client to be put on trial before the Senate on March 14, 2024 contrary to the provisions of the Legislative Houses (Powers and Privileges) Act, 2018.
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"This is a breach of Section 111 of the Constitution and Article 13 of the African Charter on Human and Peoples Rights Act.
"As you are no doubt aware, the Federal High Court had struck down the suspension of some members of the Senate and the House of Representatives who had accused the leadership of both houses of budget padding, corruption or abuse of office.
"Specifically, the court declared the suspension of the affected legislators illegal and unconstitutional.
"As a senior lawyer, you (Akpabio) ought to have drawn the attention of the members of the Senate to these decisions and several others where the high courts of some states and the Court of Appeal have held that no parliament in Nigeria has the power to suspend or expel a legislator and confiscate his salaries and allowances.
"In view of the foregoing, you will agree with us that the suspension of Senator Ningi and the denial of his entitlements are illegal and unconstitutional in every material particular.
"We are compelled to request you to ensure that the said suspension is lifted forthwith.
"However, if you fail to accede to our request seven days upon receipt of this letter, we shall not hesitate to pray the Federal High Court for the reinstatement of our client. We shall equally report you to the Legal Practitioners Disciplinary Committee for treating the judgments of the Federal High Court and the Court of Appeal with disdain."
