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FRANKFURT, March 23 (Reuters) – The European Central Bank has trimmed the carbon intensity of its 385-billion-euro stash of corporate bonds but the dwindling of purchases is slowing its progress, an ECB report showed on Thursday.

ECB President Christine Lagarde has made incorporating climate consideration into monetary policy a goal of her tenure, even as other central bankers, and some of her colleagues, have been sceptical on the matter.

In its first such disclosure, the ECB said the carbon intensity – a measure that relates a company’s emissions to its revenues and the size of the investment – of its new purchases of corporate credit had more than halved since it adopted a “green tilt” in picking bonds late last year.

The weighted-average carbon intensity of the company debt bought by the ECB in the last quarter of last year stood at just below 200 tonnes of CO2 per million in revenue generated by the company, compared to nearly 400 tonnes in the first three quarters of the year.

But the ECB has been steadily cutting the volume of its bond-buying in its effort to curb inflation, meaning the new, greener purchases were hardly making a difference in the overall stock of bonds accumulated over several years.

“While this provides an encouraging initial indication of the tilting framework’s potential, the large stock of existing holdings vis-à-vis reinvestments implies that it would take some time for the tilting to have a substantial impact on the overall carbon metrics,” the ECB said in the report.

The ECB stopped buying bonds last year and is now replacing only some of those that mature, with a view to ending those reinvestments altogether, possibly as soon as July.

The central bank of the 20 countries that share the euro currency said it could adapt its purchases “to a variety of reinvestment scenarios” and would report on its progress.

“Going forward, we will develop interim decarbonisation targets that help us stay on track towards our final targets,” ECB board member Isabel Schnabel said in the report.

Earlier this year, Schnabel had said the ECB may need to harness its multi-trillion-euro stock of bonds to step up its greening efforts – immediately bringing pushback from some of her peers.

Analysis from sustainable finance think tank Anthropocene Fixed Income Institute (AFII) showed the ECB could cut the carbon footprint associated with its corporate bond holdings by 87% if it sold just 48.3 billion euros of debt from the 25 top polluters. (Reporting by Francesco Canepa; Editing by Clarence Fernandez)