Global markets rattled over Greece debts as Osborne talks tough on EU in Brussels

British chancellor's warning about UK referendum on EU membership earns mixed reaction while fears of Greek bankruptcy mount

Global markets were rattled on Tuesday by renewed fears that Greece is close to bankruptcy while tough talk from George Osborne on the UK's position in Europe added to jitters about the region's future.

The first cabinet member of the new Conservative government to visit Brussels, the chancellor met his fellow EU finance ministers to discuss the Greek financial crisis and the region's economics. But Osborne used the opportunity to warn that Britain would be "resolute and firm" in seeking to repatriate powers before a referendum on whether the UK should quit the union.

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"The successful repayment will have reassured euro area finance ministers that the risk of a default to an official creditor has been banished only until next month. And as the repayment was largely funded by clearing out Greece's IMF reserve account, which will also need to be replenished within a month, it has once again simply added to the arrears in other parts of the Greek public finances. And so, the Greek glass still looks half-empty, and four IMF loan repayments totalling a1.6bn will come in quick succession in mid-June to provide plenty of opportunities to miss a repayment."