FRANKFURT, April 7 The size of the European Central Bank's dormant government bond purchase programme shrank to 172.5 billion euros ($236.21 billion) last week, as bonds worth 3.73 billion euros matured, the ECB said on Monday.
The decline was also due to a quarterly amortisation exercise, the ECB said.
The ECB terminated its Securities Markets Programme (SMP) in September 2012, replacing it with the as-yet-unused plan called Outright Monetary Transactions (OMT).
But because the ECB has said it will keep the bonds it acquired under the SMP until maturity, it will be years before the programme ceases to exist.
The ECB updated the contents of its SMP portfolio in February, showing it had 86.8 billion euros' worth of Italian bonds, 38.4 billion of Spanish, 25.4 billion of Greek, 19 billion of Portuguese and 9.2 billion euros of Irish government debt at the end of 2013.
The ECB will seek to take an amount equivalent to the current SMP holdings as weekly deposits from banks on Tuesday to counterbalance the buys and neutralise any threat of them fuelling inflation. ($1 = 0.7303 Euros) (Reporting by Frankfurt newsroom)