WARSAW (Reuters) - Three-times winners Germany take on feared foe Italy in the second Euro 2012 semi-final in Warsaw on Thursday, looking to set up a showdown with holders Spain who dispatched Portugal on penalties in a Donetsk nail-biter on Wednesday.

 Joachim Loew's young side have looked strong in the tournament, which ends on Sunday with the final in Kiev, but Germany have not beaten Italy in 17 years, and never at a major tournament.

 Germany can be sure of the most support in Warsaw as 20,000 fans travel east to Poland, outnumbering an expected 6,000 Italian fans at the city's magnificent river-side stadium.

 But they will be without "lucky charm" Chancellor Angela Merkel, who cheered them on wildly during their 4-2 quarter-final victory over Greece in Gdansk. Merkel will be busy in Brussels at a European Union summit.

 German media reported that during EU leaders' evening meal monitors will show the football in an adjoining room.

 Thousands of fans milled through the cobbled streets of Warsaw old town ahead of the match, feasting on traditional Polish stews and dumplings, and posing for photographs in the scenic squares.

 "Expectations are high... There were some beautiful games in the past but we always lost to Italy in the semi-finals or finals. This time it should be our turn to go further," said German fan Helmut Kiesel.

 "We certainly hope we can break the pattern this time, we have never been in a better form to do it," said Ruben Eingardner.

 Germany have been one of the favorites to take the tournament title since the beginning but Italy have vastly exceeded expectations by reaching the last four in Poland and Ukraine.

 Germany's sole concern is midfielder Bastian Schweinsteiger, who is nursing a nagging ankle injury, while Italy could be missing defenders Giorgio Chiellini, Ignazio Abate and midfielder Daniele De Rossi.

 Italy coach Cesare Prandelli pledged the Azzurri would keep their more attacking style and not sacrifice "two years' work" by reverting to a more defensive approach against Germany.

 "Germany will press us high up the pitch. We are ready for this," he told a news conference on Wednesday.

 Italy have scored only four goals in four games in the tournament, but have shone at times. Germany have won all four matches so far.

 Accompanying the German supporters are German police, who are checking whether any potentially violent fans have slipped across the border.

 "With a match like this in Poland you cannot completely rule out that some potential hooligans will come but if there are any here it would be only a tiny number and we are expecting a calm situation," a German police spokeswoman said.

 Poland's interior ministry said security services had lifted their readiness level as a precaution after a border patrol found explosives on a raft on a river on its border this week.

 There have been no major security incidents during the three-week tournament, although Polish police were criticized for allowing street fights between local hooligans and Russian fans before their June 12 clash.