Ndume gave the advice at the News Agency of Nigeria (NAN) Forum in Abuja.
He said that both arms of government were to be blamed for the seeming lack of cooperation between them, adding that it was unhealthy for democracy.
Acknowledging existence of distrust between both organs of government, the lawmaker said “it is true that the relationship between the Executive and the Legislature is not what it ought to be and it is very unfortunate.
“I think we got it wrong from the beginning. I was in the centre of this issue to a certain level.’’
He said that some misunderstanding between both arms of government began with the selection of leadership of National Assembly at the inauguration of its 8th session in 2015.
According to him, there was problem when our leadership emerged against the interest of the party.
“When we were to be inaugurated we were looking forward to direction from the Executive and President Muhammadu Buhari said he was ready to work with anybody.
“Following that, we formed an interest group called the `The Like Minds’ and struggled to take over the leadership which is normal in any political setting, and we emerged.
“I emerged as the Leader of the Senate and Dr Bukola Saraki emerged as President of the Senate and we formed our team.
“From there, the party said certain positions should be compromised including my own and we refused because I was, for example, elected by my colleagues from the North-East when the position was zoned to the area.”
He expressed concern that in spite of the fact that All Progressives Congress (APC) members formed two-third majority in the Senate, the chamber’s relationship with the Executive had not been very cordial.
Ndume called on the two arms to work together for the sustenance of democracy.
He also said that internal wrangling among senators was responsible for the problem the senate was having with the Executive, alleging that the senate had been personalised.
“Senators are afraid of expressing their opinion on what they believe in for fear of persecution, discrimination or sabotage.
“For instance, everything is in the hands of the Senate leadership or the President of the Senate.
“This is to the extent that if you go against the standpoint of the Senate President there is possibility of missing certain advantages and privileges that senators see as important; so, they compromise,” the lawmaker said.