The European Parliament and Ukrainian Rada are going ahead with the signing, but the key provisions on free trade will not be implemented until December 2015 at the earliest, BBC reported.
That delay was the main result of EU-Russia-Ukraine talks in Brussels on Friday, and it is being seen as a significant concession to Russia.
On Monday, Ukrainian President Petro Poroshenko said the ratification of the association agreement would be a "historic day".
Poroshenko, who initialled the deal back in June this year said that "de facto this is a reform programme in our country" aimed at guaranteeing "the rule of law, freedom of speech and decisive anti-corruption steps".
In November last year, thousands of Ukrainians took to streets to protest against former president Viktor Yanukovych's abrupt decision to cancel the agreement's original planned signing.