FRANKFURT (Reuters) – European Central Bank policymakers meeting on Thursday were in broad agreement that their next step will be reducing their bond purchases and discussed four options, two sources with direct knowledge of the discussion said.

Possibilities discussed by the ECB included – but are not limited to – cutting assets buys to 40 billion euros a month or 20 billion euros, with extension options including 6 months or 9 months, the sources who asked not to be named said.

Any decision should also be backed by a broad consensus, the sources said, suggesting that policy-makers are keen to avoid the repeat of the public discord that followed past rulings, when opponents at national central banks and even the ECB’s Executive Board publicly criticized decisions.

The ECB declined to comment.

Worried about the euro’s strength, the bank stayed pat on Thursday, honing in on October for the key decision after more than 2 trillion of euros worth of asset buys.

The cautious approach raises the chances that the ECB will opt to phase out quantitative easing, designed to boost growth and inflation, only very slowly next year, despite solid economic growth in the euro zone and worries about real estate bubbles in richer countries such as Germany.

Although the scenarios included specific monthly volumes and extensions, much of the focus of the discussion was on the overall amount of the purchases.

This includes the reinvestment of proceeds from maturing bonds, which will slowly rise towards 15 billion euros per month next year, the sources said.

Policymakers also agreed that interest rates will not be raised before the asset buys end, the sources said, indicating by default that any extension of the program would also push out the first rate hike.

The sources added that the so-called issuer limit, which caps any ECB buying to a third of a country’s outstanding debt, is not up for discussion because it would open the program, already under review by the European Court of Justice, for a legal challenge.

But maintaining the cap and the program’s other self-imposed constraints would limit the purchases as the ECB is already approaching its limit in several countries – notably Germany, the euro zone’s biggest economy and the ECB’s top critic.

If purchases were left unchanged, Germany could hit the limit in the first half of 2018.