(CNN) -- U.N. Secretary-General Ban Ki-moon on Tuesday praised opposition leader Aung San Suu Kyi's efforts to advance democracy in Myanmar, supporting her decision to take the oath of office for the country's parliament despite objecting to its wording.
Expressing his admiration for Suu Kyi at a news conference at her lakeside residence in Yangon, Ban said the process to improve democracy and human rights in Myanmar might be "difficult" but that there should be "no turning back."
He also said he had invited Suu Kyi, who endured years of house arrest under the country's military rulers, to visit the United Nations headquarters in New York.
Standing alongside him, Suu Kyi said that while she would like to make such a trip, she hadn't given a "definite date" yet.
She is already due to visit Norway in June to make a belated acceptance speech for the Nobel Peace Prize she was prevented from collecting in 1991 because she was in detention.
Ban voiced approval for the climbdown this week by Suu Kyi and other newly elected opposition members from their insistence that the parliamentary be reworded.
Acknowledging that it "must have been a very difficult decision," he said he believed that "real leaders demonstrate flexibility for the greater cause."
Suu Kyi also appeared to defend the decision, echoing Ban's choice of words.
"We have always believed in flexibility in the political process," she said, adding that it was the only way to achieve the movement's goal without violence.
The impasse over the oath had been preventing her and other newly elected members of her party from taking their seats in the legislature.
She and 42 other members of her party, the National League for Democracy, were elected in by-elections last month.
The NLD had asked the authorities to amend the oath to say that members will "abide by" the constitution rather than "protect" it. Party members want to revise the constitution, which they view as undemocratic.
But the government of President Thein Sein, a former military official, didn't appear to show any sign of moving to accommodate the request.
Suu Kyi said Monday that she would "take an oath for the country and for the people." She added that she had been urged to enter parliament by some parliament members and representatives of Myanmar's ethnic minority groups.
Asked whether she was concerned she may appear weak by backing down over the oath, Suu Kyi said, "I don't care."
Nyan Win, a spokesman for the NLD, said Suu Kyi will attend parliament in the capital, Naypyidaw, on Wednesday for "just one day."
Before his meeting with Suu Kyi, Ban met with top officials, including Thein Sein, on Monday and offered U.N. support.
The international organization is available to provide technical assistance for Myanmar's first census in 2014 and lend its electoral expertise in the run-up to the 2015 elections, the United Nations said.
Ban is the latest in a string of high-profile officials to visit the country as it emerges from decades of international isolation.
Myanmar's authoritarian military rulers are loosening their grip on power after decades of stifling dissent and limiting freedoms.
In the past 12 months, the government has pardoned hundreds of political prisoners, secured a cease-fire with Karen rebels and agreed to negotiate with other ethnic rebel groups.
The success of Suu Kyi and her party at the by-elections was welcomed by the United States and European Union as a sign of progress toward democracy.
The dispute over the wording of the oath appeared to create an early stumbling block in that process.
But Suu Kyi said last week that she did not want the issue to become "political," insisting that it was a "technical" problem.
Her arrival in parliament on Wednesday will illustrate the pace at which Myanmar is changing: She was released from house arrest less than a year and a half ago.
Control of parliament will not change despite the opposition's strong performance, but the entry of the NLD members will nonetheless give the party a notable presence.
Myanmar's legislature has 664 seats, more than 80% of which are still held by lawmakers aligned with the military-backed ruling group, the Union Solidarity and Development Party.
Many Western governments have taken steps to ease sanctions on Myanmar, also known as Burma, in response to its political reforms. But international officials have also cautioned that the country still has a long way to go.
Speaking last week ahead of his trip, the United Nations' Ban said that Myanmar's "fresh start is still fragile."