ATHENS (Reuters) - Greek Prime Minister Alexis Tsipras spoke by telephone to U.S. President-elect Donald Trump on Wednesday, his office said, congratulating him on his election victory and underlining the strong ties between the two countries. Trump and Tsipras discussed Greece’s role for peace and stability in the region, its efforts to tackle the economic and refugee crises and the importance of boosting strategic cooperation between the two countries.  “The two leaders agreed to maintain steady communication channels,” Tsipras’ office said in a statement, without providing further details. 