Two unions have presented more than 15,000 signatures to two MPs, calling for the government to give residency to long-term migrant workers and over-stayers.

Unite Union and the Migrant Workers Association started the petition last year, which has since gathered support from around the country.

The signatures, collected both online and at community events, were presented to Green MP and immigration spokesperson Ricardo Menéndez March and Labour MP Marja Lubeck who chairs the Education and Workforce Select Committee of Parliament.

Unite Union advocate Mike Treen said the petition essentially called on the government to use the Covid-19 crisis as an opportunity to fix long-standing problems associated with New Zealand's temporary migration system.

"Pre-Covid, New Zealand had over 300,000 people here on temporary work visas. But many of these visa holders had been sold a promise, that they would get residency eventually, that New Zealand had failed to follow through on. In fact, in the last three years it has been made much more difficult," he said.

"These workers now play an essential role in the economy and cannot be replaced in the post-Covid world. It makes sense from an economic and social justice standpoint to allow them to transition to residency if they want to."

"A few thousands more have also overstayed visas and should be given an amnesty to allow them to stay as well. Again, most of these workers were brought here on false promises and many have been subject to cruel exploitation. They have been forced to overstay their visas as a consequence so they can pay back the costs of coming here and to provide for their families back home.

"All of these workers have proven they are able to work hard and contribute to rebuilding New Zealand in the still Covid-plaugued world. It is cruel and inhumane to be arresting, jailing and deporting people at this time.

Treen said the fact that a lot of people who were not migrant workers were showing support at public events showed there was public sympathy for the proposal.

Migrant Workers Association president Anu Kaloti said migrant workers' visas should also be detached from a single employer to prevent exploitation. She said the government should also make it clear whether workers stranded overseas would be able to return, and when they could do so.

"We know that we have a government in place that has an international reputation and image of being very kind and compassionate, so we just request that the migrants are also given a small percentage of that compassion," she said.

Menéndez March said the pandemic was taking a toll on migrants and the immigration minister should take some action.

"With the powers that the minister is being granted as a result of the immigration Covid-19 response Bill, he should recognise that the pandemic is still raging and our migrant communities need support to create a pathway to residency program, so our migrant communities can fully participate in society."

Lubeck said migrant workers' contribution to New Zealand needed to be recognised but it was not an easy answer as whether to grant everyone residency.

"You really have to look across the board, and the context, to also acknowledge that there are so many issues that have arisen because of the fact that there was so much exploitation, so I do believe that there are multiple things that need to be considered."

Kaloti said she hoped the petition could contribute to the immigration debate in the House on Thursday.