In a statement issued by his media aide, Mr Paul Ibe, in Abuja, Abubakar said that the purpose of the blockade was to force a change in the leadership of the Senate.
The security personnel, who barricaded the entrance to the National Assembly complex as early as 7 a.m., barred some lawmakers of Peoples Democratic Party (PDP) from entering the premises.
He condemned “completely, this atrocity and called on all those involved to put Nigeria first and abandon this madness.
“The Constitution of the Federal Republic of Nigeria, as amended, guarantees both the independence of the legislature and Separation of Powers.
“Nigeria is a democracy not a military dictatorship and we, the people will never return to tyranny.”
The former vice president also urged President Muhammadu Buhari and Acting President Yemi Osinbajo to uphold the Constitution and law and order, which they swore to uphold on May 29, 2015.
“We warned that if what occurred in Benue last week was not checked on time, it would escalate to the federal level. Today we are seeing that warning in play.
“The Acting President, being himself, a professor of law, ought to know that setting such a precedent is an invitation to anarchy’’.
He said that there were better uses of the security forces at this time than to block the country’s legislature.
“Our people are languishing in the midst of unprecedented insecurity and nationwide killings.
“To, therefore, deploy our security forces in this present manner while Nigerians face these challenges is an abdication of responsibility, to say the least.”
Abubakar advised all Nigerians to be watchful and mobilise to defend democracy, saying that eternal vigilance is the price of liberty.