The caucus said it is convinced that a political settlement is the quickest, most effective, and honourable way of closing Mr Kanu's matter.
The South-east caucus in the House of Representatives has joined the call for the release of Nnamdi Kanu, leader of the Indigenous People of Biafra (IPOB).
Mr Kanu, who is facing terrorism charges at the Federal High Court, Abuja, has been in detention since he was rearrested in June 2021 and brought back to Nigeria from Kenya under controversial circumstances.
In a statement signed by all 43 members of the caucus on Wednesday, the lawmakers said President Bola Ahmed Tinubu should consider releasing Mr Kanu and others in a similar situation.
The caucus called for the option of an out-of-court settlement in the treason case Mr Kanu is facing.
They noted that this option would produce a "quick and responsible resolution."
"A few days ago, at the resumed hearing of the case against Mazi Nnamdi Kanu, currently pending at an Abuja Federal High Court presided over by Justice Binta Nyako, the issue of the out-of-court settlement of the matter was discussed between Mazi Nnamdi Kanu's lawyer and the Attorney General and Minister of Justice.
"According to newspaper reports, and our verified accounts of proceedings from those who were in court on that day, the court displayed sufficient support for the out-of-court settlement of this case, being one of the acceptable canons of dispute resolution in our civil and criminal jurisprudence.
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"As a caucus of the House of Representatives from where Mazi Nnamdi Kanu hails, we have taken the liberty, in consonance with parliamentary practice, to seek the support of other regional caucuses of the House of Representatives to achieve a quick and responsible resolution of the seemingly intractable Mazi Nnamdi Kanu case, a legal impasse that is undoubtedly the missing puzzle in solving the lingering security conundrum in the South-east of Nigeria.
"We, therefore, as representatives of the five South-east states in the House of Representatives, urge Mr President to consider the release of Mazi Nnamdi Kanu and his other similarly detained followers.
"We are convinced that a political settlement of this matter by way of an out-of-court settlement, as canvassed before Justice Binta Nyako, is the quickest, most effective, and honourable way of closing this difficult and painful chapter of our national history."
The lawmakers have now joined their Senate counterparts, Southeast governors, and others in calling for Mr Kanu's release.
PREMIUM TIMES earlier reported that the five South-east governors resolved to meet with the president to appeal for the release of the separatist leader.
