"If it goes wrong tonight, there could be further talks," Maas said, as quoted by The Guardian.
He, however, stressed that it was unlikely to expect any fundamental overhaul of the agreement reached by Brussels and the UK government in November.
"The agreement stands, as it is … I doubt very much that the agreement can be fundamentally reopened. If there were a better solution, it would already have been put forward," the minister argued.
The draft Brexit deal has faced much criticism both from the UK opposition and the ruling party, with several members of the cabinet having resigned over disagreements with the deal.
The deal was supposed to have been voted on by the parliament in December 2018, but the crucial procedure was postponed by Prime Minister Theresa May amid high risks that the long-sought agreement would not stand amid growing concerns over the Irish backstop, a fallback plan to avoid a hard border between the Republic of Ireland and Northern Ireland.
The European Union, earlier, said that the deal was final and was not subject to any review, despite May’s efforts to secure additional reassurances. The much-anticipated vote on the deal will take place later in the day, but there is speculation that it will not go in May's favour.