Debt-laden Greece could drag the whole eurozone into a "vortex of default, bankruptcy and an economic slump", Threadneedle's Leigh Harrison has warned.
The European Central Bank has indicated it will raise interest rates for a second time in four months at next week's meeting.
Tension between the European Central Bank and the German government has intensified as Jean-Claude Trichet hit back at the German finance minister's claims Greek government bondholders should contribute to a new aid programme.
The European Central Bank is set to raise interest rates next month in an attempt to dampen persistent inflation.
Germany is urging Greece to extend the maturity of its debt by seven years, clashing with the European Central Bank's view that forcing investors to take a loss could damage the eurozone.
Newton manager believes tightening policy now could be detrimental to growth.
Manager believes quality over defensives has been fundamental to surviving crises in markets during first six years at Threadneedle.
After admitting the MPC has lost control of inflation, Alan Wilde, head of fixed income and currency at Barings, asks if the Bank of England governor is losing his credibility.