BRUSSELS (Reuters) - European Union finance ministers will decide on Tuesday on the composition of an EU blacklist of tax havens that now includes about 20 jurisdictions but could end up with far fewer names after political horse-trading.

European Union flags flutter outside the EU Commission headquarters in Brussels, Belgium June 14, 2017. REUTERS/Francois Lenoir

Following multiple disclosures of offshore tax avoidance schemes by companies and wealthy individuals, EU states launched a process in February to list tax havens in a bid to discourage setting up shell structures abroad which are themselves in many cases legal but could hide illicit activities.

After almost a year of screening 92 jurisdictions seen as possible tax havens, EU experts have prepared a draft blacklist of those falling short of EU standards on tax transparency and cooperation.

The list contains “about 20” jurisdictions, a senior EU official said on Friday, adding that the number might be reduced when finance ministers meet on Tuesday in Brussels as some EU governments could oppose the inclusion of some jurisdictions.

The adoption of the list is deemed a certainty by many EU officials, especially after renewed public pressure triggered by the so-called Paradise Papers, the most recent revelations of widespread offshore investment by the wealthiest.

But the listing was far from a sure thing just a few weeks ago, and the official said ministers could still decide to postpone its adoption.

Divisions also remain over sanctions. To win over skeptical governments, the most effective countermeasures, such as a levy on transactions to tax havens, could be left to national discretion, a move that might create loopholes.

Other EU sanctions, such as the freezing of European funding, cause less controversy but are regarded as much less effective in persuading the richest tax havens to change course.

The official said a second “grey” list had been drawn up to include jurisdictions who are not compliant with EU standards but have committed to change their tax rules.

This list is seen as a victory for countries who are cool about the process, like Luxembourg or Malta, because several jurisdictions deemed as currently acting as tax havens will avoid the reputational risks associated with blacklisting.

The grey list could remain undisclosed if ministers so decided. The official said around 20 other countries are on the grey list.

EU finance ministers are also expected to adopt a common position on taxation of tech corporations like Amazon or Facebook. They have been accused of paying too little tax in the EU by rerouting the booking of their profits to low-tax nations where they have set up headquarters, like Luxembourg or Ireland.

The draft text of the conclusions on the agenda for Tuesday’s meeting has been watered down under pressure from reluctant countries.