By Erik Kirschbaum
BERLIN (Reuters) - Germany's Greens threw up a new hurdle to a possible coalition with Chancellor Angela Merkel's conservatives on Wednesday by condemning her government's refugee policies after the migrant boat disaster off the Italian island of Lampedusa.
The Greens, who will hold exploratory talks with the conservatives on Thursday evening, were already skeptical about helping Merkel form a government for her third term because of differences on energy, tax and social issues.
Then they added changes to refugee rules to their wish list following Interior Minister Hans-Peter Friedrich's rejection of calls for Germany to take in more refugees after about 300 African migrants died last week crossing the Mediterranean.
"Humanitarian refugee policies are a central issue for us," said Greens parliamentary leader Katrin Goering-Eckardt.
"Friedrich's position is simply unacceptable. I can only imagine (a coalition) if this position is changed. Germany needs to take in more refugees," she told a news conference.
Friedrich, who is from the Bavarian Christian Social Union (CSU) which opposes a coalition with the Greens, said Germany absorbs more refugees than any other European Union country - some 100,000 this year.
The minister said that amounts to 946 refugees per 1 million residents in Germany compared to 260 per 1 million in Italy.
Germany was long open to refugees because in the Nazi era German opponents of Adolf Hitler obtained asylum abroad, including former chancellor Willy Brandt. The right to asylum is in Germany's constitution. But Germany tightened the rules after the annual number rose to over 500,000 in 1993.
The Greens have traditionally supported liberal refugee policies. But it was nevertheless a surprise to see the party, which had a poor 8.4 percent result in the September 22 election, include that issue in Thursday's coalition talks.
Merkel's conservatives emerged from the vote as Germany's dominant force but, with 311 of the 631 seats in the Bundestag (lower house), they lack a majority and need a coalition ally. They first held talks with the Social Democrats (SPD), who won 193 seats. The Greens won 63 seats and the radical Left 64.
The Greens at first signaled that they would prefer to stay in opposition while the SPD formed a government with Merkel - which is still the most likely outcome of coalition talks.
But many moderates in the Greens and conservatives hail it as a historic chance for the erstwhile rivals to join forces.
"We're ready to take over government responsibility but we're going into these talks with a lot of skepticism," said Goering-Eckardt.
(Editing by Stephen Brown and Mark Heinrich)