Bankers expect more than €100bn ($146bn) of bonds to hit the European primary market this month, one of the most important months in the debt calendar which traditionally sets the scene for the health of the rest of the year.

The figure would surpass last September’s total, and follows record corporate bond sales volumes for August. But bankers caution that an issuance surge may be as much a sign of weakness as strength, as companies, financial institutions and public sector issuers cram in funding ahead of what they fear could be more difficult conditions ahead.