Pope Benedict has used a trip to southern Italy to urge Italians, who are embroiled in heated debate on immigration, to show solidarity with the poor and suffering who come to their shores seeking a better life.

The Pope made his appeal during a weekend trip to this southern port city which has for centuries been a historic arrival point for immigrants and refugees.

"In recent years, newspapers and television have shown us pictures of refugees landing in Brindisi from Croatia, Montenegro, Albania and Macedonia," he told a crowd in the city centre on Saturday night, thanking the city for its generosity towards them.

In a sermon at an open-air Mass in the port where immigrants from the Balkans arrived in large numbers in the 1990s, Benedict returned to the theme of compassion for those in need. He told his listeners that Christ taught love and charity for the weak and the poor.

"Christian compassion has nothing to do with pietism (exaggerated or affected piety) or with relying on handouts," he told a crowd of some 70,000 on the dockside.

"Rather, it is synonymous with solidarity and sharing," the 81-year-old Pope told the congregation.

HOT POLITICAL TOPIC

Immigration was one of the hottest political topics at an April general election which was won by conservative Silvio Berlusconi whose allies include the anti-immigrant Northern League and the right-wing National Alliance party.

The Church has expressed concerns about a crackdown on immigration which includes new legislation that would make illegal immigration a crime punishable with jail time.

Many hundreds of migrants arrive in Italy every week, often picked up at sea by Italian authorities while crossing in overcrowded and poorly equipped boats from North Africa.

During his trip to Puglia, the Pope has sought to inspire the faithful to spread the word in a region blighted by poverty and crime.

"I know, in particular, the grave weight that burdens the future of more than a few of you caused by the dramatic phenomenon of unemployment which above all hits the young men and women of the south (of Italy)," he said in his speech on Saturday night.

The Pope also saluted the work of the United Nations, which has a major peace-keeping and emergency food aid logistics base near the city which he called a "port of salvation for every person and all humanity".