US President Barack Obama was heckled as he urged both sides in the abortion debate to find common ground. Mr Obama asked for a "fair-minded" discussion of the divisive issue in a speach at the most prestigious Catholic university in the US. The decision by Notre Dame University in Indiana to confer an honorary degree on Mr Obama and invite him to speak sparked petitions and days of protests. Critics who said Mr Obama's support for abortion rights violated Catholic Church doctrine had sought to have the invitation withdrawn but the university refused. Interrupted by hecklers, Mr Obama said he recognised the strong emotions stirred up by the abortion debate but he urged the two sides to try to find common ground like preventing unintended pregnancies. He said: "I do not suggest that the debate surrounding abortion can or should go away. Each side will continue to make its case to the public with passion and conviction. But surely we can do so without reducing those with differing views to caricature." He added: "Let us work together to reduce the number of women seeking abortions. Let's reduce unintended pregnancies. Let's make adoption more available. Let's provide care and support for women who do carry their child to term." His appearance was mostly warmly welcomed by the crowd, which gave him several standing ovations.