The latest development is believed to be due to a meeting between Ali and Senate President, Bukola Saraki on Tuesday, March 14.

President Muhammadu Buhari is also said to have intervened in the battle causing Ali to visit Saraki in a bid to seek peace, according to a Vanguard report.

Buhari also reportedly warned his appointees not to overheat the polity by creating avoidable friction between the Executive and the Legislature.

Ali has been involved in a war of words with lawmakers over his refusal to wear the agency’s uniform.

“No! I was not appointed Comptroller General of Customs to wear uniform. Does uniform work or the person behind the uniform?” he said while speaking to TVC in a video published on March 10.

“Am I doing my job or not? I think that should be what should worry the National Assembly,” he added.

He also initially refused to appear before the Senate on Wednesday, March 15, saying that he had a meeting to attend.

“I'm directed to acknowledge the receipt of your letter no NASS/CS/8S/09/29 of 9th March 2017 on the above subject matter,” a letter from Ali’s office to the Senate read.

“I have been further directed to tell you that the date given to the comptroller-general of the Nigerian Customs Service Wednesday 15th March 2017 to brief the senate in plenary on the retrospective duty payment of vehicles in Nigeria has coincided with the fortnightly meeting of the NCS management,” it added.

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The Senate however warned him to either appear before it in uniform to resign his position.

The Customs’ boss explained that he was not required to wear the uniform because he had served as a soldier and could not be expected to wear two separate uniforms.

Ali was summoned by the Senate over a plan by the NCS to collect duties on old vehicles.