The lawyer said the NLC president informed the secret police of his plan to honour its invitation next Monday.
Maxwell Opara, a lawyer to the President of the Nigerian Labour Congress (NLC), Joe Ajaero, said the labour leader informed the State Security Service (SSS) about his trip to United Kingdom for an official engagement.
He said the SSS had invited Mr Ajaero a couple of days ago via a telephone call but that he told the secret police that he would honour the invitation on Monday 16 September upon his return from the UK to Nigeria.
"They (SSS) invited him on the phone. He told them that he was engaged with the World Trade Union Congress. He had committed to meeting with the SSS on Monday when he returns from the UK," Mr Opara told PREMIUM TIMES in a telephone interview on Monday.
Mr Ajaero was arrested earlier on Monday at the Nnamdi Azikiwe International Airport, Abuja on his way to the UK.
In a statement, the NLC said he was billed to address the global gathering of workers on behalf of Nigerian workers at the TUC in the European country.
NLC spokesperson, Benson Upah, who signed the statement, said condemned Mr Ajaero's arrest.
"The arbitrary arrest of Joe Ajaero shows an escalating crackdown on human rights and restrictions on civic space by the government of President Bola Tinubu," the statement said.
Alleged plot to sack Ajaero
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Mr Opara accused the Nigerian government of attempting to undermine Mr Ajaero's advocacy and his leadership of the NLC through his arrest.
According to the lawyer, the arrest is part of a broader strategy to disrupt the NLC president's efforts on behalf of Nigerian workers.
Mr Opara criticised the SSS for allegedly misrepresenting Mr Ajaero's schedule, accusing the government of deliberately attempting to remove the labour leader from office and replace him with somebody more aligned with its interests.
"The government wants to push him out," Mr Opara said. "The SSS claimed Mr Ajaero was invited, despite his clear communication about his availability. This is a deliberate attempt to disrupt his work.
"The timing and nature of this arrest suggest an effort to weaken Mr Ajaero's influence and consolidate control over the labour movement," he added.
The SSS could not be contacted for comment because its spokesperson, Peter Afunanya, was recently redeployed and has not been replaced.
The NLC, TUC and the Amnesty International have since demanded the immediate and unconditional release of Mr Ajaero, who had been invited twice by the police in the last few weeks.
