Ms King also told delegates that climate change had to be tackled. She said this would pose challenges to workers in some areas such as energy . She called for a "just transition" away from fossil fuels which would protect the livelihoods of workers and their communities.
Ms King said there was an existential threat to our planet on a scale that we have never faced before, at a national or a global level.
"It requires a clear, concerted, coherent and strategic response. It is not optional. There are no jobs on a dead planet," she said.
'the Paris Agreement signed in 2015 means that action on climate change has been transformed from an optional policy extra for the governments, into a binding, international obligation.
"In addition this agreement also explicitly requires that signatory governments must ensure that the policy response to climate change is governed by the principles of a just transition."
Greenhouse gas emissions
Ms King said that a priority on the island of Ireland must be to reduce greenhouse gas emissions over coming decades and hasten an energy transition beyond fossil fuels.
'this will pose particular challenges for workers in the energy sector," she said.
Ms King said Ictu had considered the need for a "just transition" at a conference in Tullamore and had, in particular, reflected on the future for workers within Bord na Móna, and some sections of the ESB.
"At its simplest, a just transition is defined by trade unions as one which secures the future and livelihoods of workers and their communities in the transition to a low carbon economy," she said.
"As we understand the term, it is about seizing new opportunities and sharing the benefits of change, through creating better jobs, better social protection, more training opportunities and greater job security for all those affected by global warming and climate change policies."
Ms King said there was strong international evidence, such as in Scotland, Germany and Australia that such transition , properly planned, can result in decent work and new opportunities.
"We are calling for the immediate establishment of a national Just Transition Forum, which would be tasked with developing the appropriate measures to ensure that neither the Bord na Móna workforce nor the local communities in the Midlands are left behind."
Unite represents workers in Britain, Northern Ireland and in the Republic of Ireland.
Ms King told delegates that the trade union movement had grave concerns about the potential impact of Brexit on the rights of workers, the negative impact on trade and jobs and the Belfast Agreement.
"We are very concerned about the possibility of the re-introduction of the Border on the island of Ireland but we are equally concerned that we must also avoid a border within the UK, between Britain and Northern Ireland and any economic border between these islands."