Greece on Wednesday promised it would start pension and tax reforms next week, as demanded by creditors, in return for a three-year eurozone loan to drag its financial system back from the brink of collapse.

"We propose to immediately implement a set of measures as early as the beginning of next week including: tax reform related measures; pension related measures" if the loan from the European Stability Mechanism (ESM) was forthcoming, the finance ministry said in a letter to the eurozone bailout fund.