Greek leftist leader Alexis Tsipras (ah-LEHK-sees SEEP-rahs) was sworn in as the country's prime minister on Monday following an unexpectedly clear election victory for his second term in parliamentary elections on Sunday. Tsipras took a civil oath of allegiance to the Greek constitution, in a break from common practice which is normally in the presence of religious leaders. After the swearing in ceremony, he walked the short distance to the Prime Minister's office for the official handover with the interim premier. (SOUNDBITE) (Greek) GREEK PRIME MINISTER, ALEXIS TSIPRAS, SAYING: "I am returning after a few days, almost a month, to the prime minister's office with the memory of a difficult period behind me, of tough negotiations, and the battles fought right here in this room, but also bringing with me optimism and the faith that when, at some point, I will leave this office again, these memories will be forgotten and replaced by better, more constructive ones." Tsipras first came to power January but then called for new elections after his party split a month ago. He says his victory gives him a mandate for a full four-year term, extraordinary in a country that has gone through five general elections in six years amid major financial turmoil.