Greek crisis brings eurozone to a crossroads | Letters

We call on David Cameron to support the organisation of a European conference to agree debt cancellation for Greece and other countries that need it, informed by debt audits and funded by recovering money from the banks and financial speculators who were the real beneficiaries of bailouts (Greek leader calls last ditch referendum on bailout, 27 June). We believe there must be an end to the enforcing of austerity policies that are causing injustice and poverty in Europe and across the world. We urge the creation of UN rules to deal with government debt crises promptly, fairly and with respect for human rights, and to signal to the banks and financiers that we won't keep bailing them out for reckless lending.
Frances O'Grady General secretary, TUC
Len McCluskey General secretary, Unite the Union
Paul Kenny General secretary, GMB
Manuel Cortes General secretary, TSSA
Sarah-Jayne Clifton Director, Jubilee Debt Campaign
Paul Mackney Chair, Greece Solidarity Campaign
Nick Dearden Global Justice Now
Owen Epsley War on Want
James Meadway New Economics Foundation
Ann Pettifor Prime Economics
Diane Abbott MP
Dave Anderson MP
Richard Burgon MP
Jeremy Corbyn MP
Jonathan Edwards MP
Roger Godsiff MP
Harry Harpham MP
Carolyn Harris MP
George Kerevan MP
Ian Lavery MP
Clive Lewis MP
Rebecca Long-Bailey MP
Caroline Lucas MP
John McDonnell MP
Liz Mcinnes MP
Rachael Maskell MP
Michael Meacher MP
Grahame Morris MP
Kate Osamor MP
Liz Saville-Roberts MP
Cat Smith MP
Chris Stephens MP
Jo Stevens MP
Catherine West MP
Hywel Williams MP

" For some time it seemed that an agreement between Greece and the troika might be reached. As it became clear, four days before Tuesday's deadline, that no such agreement will be reached, Alexis Tsipras is right to ask the Greek people whether they would support him in sticking to the policy on which he was elected or whether they are prepared to give in to the troika's terms. The troika will not allow Greece these five or six extra days to hold the referendum. If the Greeks were to support Tsipras, Greece would have to default with all the dire consequences not only for Greece but also for the eurozone, and that disaster would have been put off by these few days. But if the result of the referendum were to accept the troika's terms, the crisis for Greece and the eurozone would be ended, certainly in the short term and possibly in the longer term also. It seems insane to throw that possibility away, however exhausted and exasperated the troika is. It seems that the troika now actually wants to make sure there is a Grexit.
Ralph Blumenau
London

Related: Greek crisis live: Banks to stay shut on Monday - reports