If it does its best in this final stage, Croatia can expect the completion of the negotiations in early 2011, Westerwelle said in a speech he delivered in Zagreb after meeting Croatian Prime Minister Jadranka Kosor.
He described 2011 as a great year for Croatia also because next year the country would mark the 20th anniversary of its independence.
Praising Croatia for investing a lot of effort in its accession to the EU, the German minister said that Europe meant more liberty, more security and more prosperity.
He recalled that Germany had supported Croatia on this road from the very start. In this context, he said that Hans-Dietrich Genscher, who served as German Foreign Minister from 1974 to 1992, had been subjected to much criticism for lobbying for the international recognition of Croatia.
"Despite much opposition, he stuck to his belief, and the history proved he and his vision were right," Westerwelle said.
He commended Croatia's progress in the fight against corruption, adding that some work still remained to be done in overhauling the judiciary.
Expressing optimism about Europe's future, the German official described the EU as the embodiment of the rule of law, human dignity and individual rights and freedoms, notably the rights and freedoms of minorities.
Before this speech, Westerwelle met with his Croatian counterpart Gordan Jandrokovic who introduced the German official to the audience in the city's Narodni Dom hall.
Addressing the audience, the Croatian minister said Germany had backed Croatia since the very start of its independence.
"Germany supported Croatia's admission to NATO, and has been supporting it in the final stage of its negotiations with the EU," Jandrokovic said.
Croatia is the first stop of Westerwelle's tour of the region. He will also visit Bosnia-Herzegovina, Serbia and Kosovo.