Business correspondent, BBC News
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Germany's Frankfurter Rundschau says that the High Court decision is "a heavy blow for May's government", while a headline in the German tabloid Bild reads: "Theresa May's Brexit plans in danger".
France's Les Echos declares that "On Thursday, the government hit an iceberg called the High Court of Justice. Enough to sink the ship Brexit? Or just rock it slightly?"
Another French paper, Liberation, opts for a less dramatic metaphor, saying that "This is not a setback for Brexit but a stinging rap on the knuckles for the government of Theresa May."
But the Italian business daily Il Sole 24 Ore believes that "the judges of the British High Court have detonated a new bomb under the fraught separation of London from Brussels."
House of Lords
Shadow communities and local government spokesman Lord Kennedy of Southwark says the UK has "the fourth-lowest home ownership rate in the European Union", with only Denmark, Austria and Germany having lower rates.
He claims that young people's wages are lower than they were 10 years ago while rents have risen.
The Labour peer says he grew up in social housing in Southwark, in south London, adding: "Council housing was very good for us. It was a step up."
He argues that, if more housing with affordable rents is not made available, "we're going to reap a terrible reward".
House of Lords
Peers now begin their debate on the status of creative subjects on A-Level curricula.
Earlier this month AQA, the last exam board to offer history of art at A-level, announced it would be dropping the subject.
This year the A-level was taken by only 839 students and 721 at AS-level. AQA said it was struggling to recruit enough specialist examiners for the subject.
Lib Dem Baroness Brinton is opening the debate and worries that the creative subjects are being undermined at the expense of STEM subjects.
She asks the government if it still believes that students need a broad range of choice when choosing what to study at A-level.
The Secretary of State for Exiting the European Union insisted the government would appeal the High Court's Brexit ruling.
House of Commons
Labour frontbencher Jack Dromey is finishing off the debate. He's drawing attention to what he calls "unacceptable age discrimination", the fact that the National Living Wage applies only to over 25s. He says an under-25 can legally be paid £6.95 an hour, the National Minimum Wage, for the same work a colleague aged 25 or over has to be paid £7.20 an hour for.
He says his party has a "more ambitious approach" to the issue, and is advocating a £10-an-hour minimum wage by 2020.
He says for workers the "dignity of labour is paramount" and they should be able to "enjoy life" and "not have to scrimp and save".
European Commission President Jean-Claude Juncker tells the BBC he won't be commenting on the UK government's High Court defeat over Article 50 because he has a phone call lined up with Theresa May on Friday morning.
The former chancellor's tweet followed PM Theresa May's appearance at the Spectator Magazine awards last night:
David Davis's claim that an Act of Parliament would be needed before triggering Article 50 was the "logical conclusion" of Thursday's High Court judgement, the prime minister's spokeswoman has said.
But she added that "the key thing is that we are appealing - we don't accept the court's judgment".
Theresa May is set to call EU Commission President Jean-Claude Juncker to make it clear she intends to stick to the timetable for triggering Article 50 in March, the spokeswoman said.
She also stressed that the judgement wouldn't change the date of the next election, adding: "There shouldn't be an election until 2020 and that remains her [Mrs May's] view."
The nations and regions should be given powers allowing them to negotiate directly with the European Union over parts of the Brexit settlement, Gordon Brown has suggested.
In a speech in London, the former prime minister said the UK appears united in name only and needs wholesale constitutional reform to ease the strains caused by the referendum vote.
Scrapping the House of Lords and replacing it with an elected senate to represent different areas in the UK should be considered, he told the Fabian Society.
Mr Brown called for a constitutional convention to be set up that would look at giving Scotland, Wales, Northern Ireland and the English regions control over areas grabbed back from Brussels, such as agriculture and fisheries, when Britain quits the bloc.
The government needs to be more transparent about its objectives for Brexit - and ensure Parliament can scrutinise and vote on them, a senior Conservative has claimed.
Andrew Tyrie, chairman of the influential Commons Treasury Select Committee, said this would enable a broad-based public consent for the UK's future relationship with the EU.
Quote Message: The UK is leaving - a public debate is needed about where we want to arrive. Before taking off, it is always a good idea for the pilot to discuss with the passengers and crew where they might want to land."
Mr Tyrie added that clarifying the UK's future relationship with the EU would also "reduce the economic damage caused by uncertainty".
The government will be forced to produce a full Act of Parliament in order to trigger Article 50 unless it can overturn the High Court ruling, David Davis has indicated.
The Brexit secretary insisted "the people are sovereign" as he defended the government's decision to appeal against the judgment.
A full Act of Parliament would require the agreement of both the Commons and the Lords and could lead to multiple attempts to amend the legislation - causing further difficulties for the government.
Mr Davis said Parliament had already put the decision on leaving the European Union into the hands of voters - and MPs and peers should not frustrate that.
He said the result of the referendum "must be respected", adding:
Quote Message: Parliament voted by six to one to give the decision to the people, no ifs or buts, and that's why we are appealing this to get on with delivering the best deal for Britain - that's the best deal for growth, the best deal for investment, the best deal for jobs. The people want us to get on with it and that is what we are going to do."
Scotland's First Minister Nicola Sturgeon says the High Court judgement on Article 50 is "hugely significant" and underlines "the total chaos and confusion at the heart of the UK government".
She says the government's refusal to allow a vote in the Commons exposes the fact it does "not have a coherent position".
Ms Sturgeon argued that as Scotland voted to remain in the EU, her job is "to protect our place in Europe and the single market as far as I possibly can".
SNP MPs "will not vote for anything that undermines the will of the Scottish people", she added.