In a statement, current EU president Portugal noted international observers had reported progress, despite continued failure to meet a number of democratic standards.
It said the EU was willing to help Kazakhstan meet its commitments to improve electoral procedures.
According to preliminary results, President Nursultan Nazarbaev's Nur Otan party received 88 percent of the vote on August 18. No other parties crossed the 7 percent barrier needed to make it into the Mazhilis, the lower house of parliament, leaving Nur Otan with all 98 seats.
Washington Joins Criticism
In its reaction, the U.S. State Department said the elections displayed "serious shortcomings."
A U.S. State Department spokesman, Gonzalo Gallegos, said that while Kazakhstan had made progress toward democratic reform, the election fell short of international standards. He said the 7 percent barrier for parties to win seats was too high, and criticized other election rules that allow the government to appoint some representatives to the lower house.
The Organization for Security and Cooperation in Europe (OSCE), which monitored the vote, has also said that the election demonstrated progress toward democracy, but did not meet international standards, partly due to a lack of transparency during the vote count.
The leader of the opposition All-National Social Democratic Party, Zharmakhan Tuyaqbay, told RFE/RL's Kazakh Service that the election results were fraudulent, and said his party will challenge the results in court.
Meanwhile, Kazakh President Nursultan Nazarbaev described the vote as free and fair, and said there is "no tragedy" in a single-party parliament.
(compiled from agency reports)