Madonna is due to complete her tour on 2 September in Israel
Madonna has said she was "compelled" to comment on the discrimination against Romany Gypsies while on stage in Romania, despite being booed by fans.
The 51-year-old was jeered by the audience in Bucharest after saying the discrimination "made me feel very sad".
Publicist Liz Rosenberg said Madonna made the comments after being made aware of the prejudice towards Romany people in Eastern Europe.
The star uses a group of Roma musicians on her Sticky and Sweet tour.
Madonna paused during her two-hour show to say: "It has been brought to my attention, that there is a lot of discrimination against Romanies and Gypsies in general in Eastern Europe - it made me feel very sad."
"We don't believe in discrimination, we believe in freedom and equal rights for everyone."
Jeers and cheers
The star then received more boos when she mentioned prejudice against homosexuals and others.
Rosenberg said Madonna had told her there were cheers as well as jeers from the 60,000-strong crowd.
"Madonna has been touring with a phenomenal troupe of Roma musicians who made her aware of the discrimination toward them in several countries so she felt compelled to make a brief statement," she added.
Concert goer Ionut Dinu, 23, said: "I jeered her because it seemed false what she was telling us. What business does she have telling us these things?"
Romania has the largest number of Roma in Eastern Europe.
Nearly half of Europe's estimated 12 million Roma claimed to have suffered an act of discrimination over the past 12 months, according to a recent report by the EU Fundamental Rights Agency.
The agency says Roma face "overt discrimination" in housing, health care and education.