There is little optimism on show in European press commentaries on the formal start of Britain's departure from the EU.
"Divorce hurts", warns Germany's centre-right Frankfurter Allgemeine Zeitung over a photograph of Winston Churchill's brooding statue on Parliament Square. Its London correspondents are not alone in seeing "little chance of a trade agreement by 2019", and predict that British citizens will be nearly €5,000 ($5,400; £4,300) worse off a year after Brexit.
The paper's economics correspondent Ralph Bollman is more interested in what Brexit will cost Germany, given that the EU losing its third-largest economy will "also weaken Germany's voice in the world". But overall he thinks "highly-indebted Britain has the most to lose from uncertainty over a friendly deal with Brussels".
Several papers find piquant symbolism in the launch of the new pound coin this week. Bjoern Finke, the London economics correspondent of Munich's Sueddeutsche Zeitung, compares the "fresh sparkle" of the coin to the pound's "lacklustre foreign exchange performance since the Brexit vote".
He also warns that the "divorce could turn ugly" as Brussels's demand for up to €60bn in compensation will be opposed by the anti-EU wing of the Conservative Party. "British arrogance will hike the cost of Brexit", he concludes.
France's centre-left Le Monde runs "the consequences of the break" as its top front-page story, seeing Mrs May starting from a "position of strength at home, given the decay of the Labour Party", but facing "complex negotiations over expatriates, access to the single market, and control of borders".
Its London and Brussels correspondents agree with Brexit Secretary David Davis that the talks could be "the most complicated of all time", especially as EU chief negotiator Michel Barnier wants "no trade talks until the matter of expatriates, borders and Britain's outstanding budget contributions are settled".
EU nationals in Britain in particular have "rushed en masse into the uncertain and Kafkaesque procedures of acquiring resident status, fearing as they do being used as bargaining chips", they say.
France's conservative Figaro captions a photo of Mrs May with the words "the day Britain bids farewell to Europe".
Its London correspondent Florentin Collomp sees "two years of arm wrestling" ahead and remarks that "the ball is now in Brussels's court, as it must respond and set the pace".
He sees the complex set of issues to be sorted as "potentially explosive", given that Mrs May will be "torn between the compromises she will have to make to her former partners, and the pressure at home of her party's Europhobes and the press".
Mr Collomp also raises the "danger of the disintegration of the UK" as Mrs May "cannot put off Scottish demands for a second independence referendum indefinitely".
He warns that "Fires are smouldering in Northern Ireland too", as the power vacuum in Stormont is "playing into the hands of supporters of the reunification of Ireland".
'Leap into the unknown'
Italy's Corriere della Sera says "Brexit is under way, but without walls", declaring that the negotiations will set "no predetermined ceilings for EU migration, but rather decisions sector by sector".
Its London correspondent Luigi Ippolito says Britain is entering "uncharted territory", and La Repubblica's Enrico Franceschini agrees it is a "leap into the unknown".
He singles out freedom of movement of labour as one of the "major stumbling blocks in the path of the negotiations".
The front page of Poland's Gazeta Wyborcza declares that "today Brexit begins" and its London correspondent Maciej Czarneck, like so many others, dubs it a "journey into the unknown".
The paper's coverage focuses on the fate of Polish workers in Britain and its account of the Scottish independence question is headed "what does this mean for Polish immigrants?"
Rzeczpospolita looks at Britain's possible bargaining gambits, saying "Brussels fears Britain will use divisive tactics to try to obtain softer Brexit terms by offering to accommodate privileges for Poland's many citizens in the UK… or Dublin's desire for a virtually open border with Northern Ireland".
Romania's Hot News site fears for the future of the Union, lamenting that "Losing the British is the hardest blow the EU has received in six decades of intense efforts to build European unity. The results of these negotiations will determine the future of an economy worth $2.6tn".