Tata Steel job cuts devastating blow, says Carwyn Jones
First Minister Carwyn Jones has said steel job cuts could have been avoided if UK ministers had acted sooner.
Port Talbot will suffer more than half of the 1,050 UK job cuts announced by Tata Steel on Monday.
Mr Jones said it was a "devastating blow to the community and the wider economy", announcing a task force.
Welsh Secretary Stephen Crabb said the UK government would work with Tata to "ensure they remain a significant presence in south Wales".
"Workers and their families at the plant face a deeply worrying time, and our priority is to help those likely to be affected," Mr Crabb said.
"The UK government will keep doing what it can to support a steel industry suffering intense pressures from cheap steel imports and a global slump in prices."
But he told BBC Wales the idea of government taking a stake in Tata Steel was "intellectually lazy".
"They're the ones with the expertise to know how to create value and create profit in a very challenging steel industry," he said.
Business Minister Anna Soubry later told MPs in the House of Commons steel was a "vital industry".
She said the UK government was doing all it could to help Tata Steel find a "sustainable future", within the limitations of EU rules on state aid.
But the first minister blamed the UK government for failing to tackle the industry's high energy costs and cheap Chinese exports.
"I don't think the UK government took seriously the issue of below-cost supply on the market and lobbied effectively in order to provide protection there," Mr Jones said.
"I don't think it's taken action quickly enough over energy prices."
A Welsh government taskforce, chaired by Economy Minister Edwina Hart, will meet on Wednesday to discuss a plan to help workers, he added.
Aberavon Labour MP Stephen Kinnock said the Port Talbot plant was the "beating heart of our economy, and our community".
"Our thoughts are with those who will be most directly affected by this terrible news, and we must now do all we can to rally around them and their families," he said.
Plaid Cymru economy spokesman Rhun ap Iorwerth called on the Welsh government to "look with urgency at all options" to support the steel industry, including taking a temporary stake in Tata Steel to safeguard the remaining jobs.
"There is a bright future for steel in Wales, but urgent help is needed to get us through these difficult times," he said.
For the Welsh Liberal Democrats, South Wales West AM Peter Black said: "These are well-paid jobs and will prove difficult to replace."
"If the two governments do not act quickly and decisively together to start to put things right then I fear that there may well be more job losses," he added.
UKIP Wales leader Nathan Gill claimed ministers were "impotent" due to membership of the European Union.
"They can't offer state aid, they are limited in reducing energy costs and they can't act to prevent the dumping of cheap Chinese steel, all because of the EU," he said before the announcement.