The Dutch senate is set to vote in favour of the controversial EU treaty with Ukraine on Tuesday thanks to the support of the CDA, the Volkskrant said.

Christian Democrat senators have a ‘positive attitude,’ Elco Brinkman, the party’s leader in the senate, told the paper.  CDA MPs voted against the treaty when it was voted through by the lower house in February but the support of CDA senators is seen as crucial to have the treaty approved.

Over 60% of Dutch voters who took part in last year’s referendum on the treaty voted against it. Even though the referendum was advisory, most MPs said the decision had to be respected.

However, in December, prime minister Mark Rutte won the support of the 27 other European leaders for a supplementary declaration to the Ukraine treaty which makes it clear what the agreement actually entails.

Rutte has said that if the Netherlands fails to ratify the treaty, it could have serious implications for the stability of Europe.