"That's our first priority ... to make sure that they're looked after, because the last thing we want is a situation down at that port which would just be a huge health and safety risk.''
Mr Pearson said lifting the lockout would depend on assurances from the union.
It would also depend on the outcome of mediation with the union, which comes after an Employment Court judge urged the port to resume talks.
Mr Pearson said the port wanted to start the mediation process as soon as possible.
"For us, to actually go ahead with this means that we can finally get some conclusion to this longstanding battle that's been going on, which is causing tremendous disruption to the supply chain and to our customers.''
Mr Pearson said the lockout was separate to the good-faith bargaining the port was entering into with the union over the collective employment agreement.
Council of Trade Unions (CTU) president Helen Kelly said the union members were entitled to return to work and the lockout was unlawful.
"And for Mr Pearson to come up with another reason - continuing to accuse these very, very good people of being thugs and being violent - is absolutely outrageous. If he has got any evidence of this he should give it to the police,'' she told Radio New Zealand.
"There is no evidence of threats. Honestly, there's 300 workers - what, they're all running around threatening people?
"They haven't seen these workers inside the gate for three weeks, they've been on strike.''
Ms Kelly said the union members were entitled to work and the CTU was seeking a court injunction this morning to "force the court to obey the law''.
The global wharfies union, the International Transport Workers' Federation (ITF), condemned the lockout overnight as "unbelievable, unlawful and practically suicidal''.
It has formed an international crisis mission that it says would investigate "the management-engineered crisis'' and meet with Auckland Mayor Len Brown.
It would also further investigate the use of labour supply companies to break strikes and drive down conditions in the ports industry, both in New Zealand and internationally.
The crisis mission is being organised by ITF's fair practices committee - a group made up of global docker and seafarer union representatives - from ITF's London headquarters.
ITF president Paddy Crumlin said the dispute was "like watching a car crash in slow motion''.
"Just when a negotiated settlement was within reach they have trampled on those hopes and issued a lock out notice,'' he said.
"We are today calling on our members to use all lawful means to convince Auckland's mayor and council to step in and replace those in the Ports of Auckland board responsible for these actions with members who are willing to run this important asset properly for the benefit of the city of Auckland and its citizens.''
Mr Brown yesterday said he had appointed lawyer Alan Galbraith QC to track the legal moves in the crisis.
"The two sides need to get into mediation and get this sorted out,'' he said.
"The court has put forward a process and I expect both sides to abide by that process.''