* Pope had urged uniting 'with no victors or vanquished'
* Follows-up goodwill message to China
* Meets with South Korean 'comfort women' (Recasts with pope's departure, adds message to China)
By Ju-min Park and Tony Munroe
SEOUL, Aug 18 (Reuters) - Pope Francis on Monday called for peace and reconciliation on the divided Korean peninsula and sent a further message of goodwill to China, wrapping-up a five day trip to South Korea and the first papal visit to Asia in 15 years.
Before a Mass on Monday at Seoul's Myeongdong Cathedral, Francis prayed with a small number of "comfort women", who were forced to work as sex slaves for Japanese soldiers occupying the country before and during the World War Two.
"Today's Mass is first and foremost a prayer for reconciliation in this Korean family," Francis said, following up on an impromptu prayer on Friday when he urged Koreans to work to unite as one family, "with no victors or vanquished".
The 1950-1953 Korean war ended in an armed truce that leaves North Korea and South Korea in a technical state of war.
A group of defectors from North Korea and relatives of South Koreans abducted by the North were invited to the mass, which was attended by South Korean President Park Geun-hye.
North Korea turned down an invitation from the South Korean Catholic church for members of its state-run Korean Catholic Association to attend Monday's Mass, citing the start of joint U.S.-South Korean military drills, also due to begin on Monday.
"Let us pray ... for the emergence of new opportunities for dialogue, encounter and the resolution of differences, for continued generosity in providing humanitarian assistance to those in need, and for an ever greater recognition that all Koreans are brothers and sisters, members of one family, one people," Francis said.
Near the conclusion of Monday's Mass, a choir sang, "Our wish is unification."
As the pope's plane entered Chinese airspace on its return flight to Rome, Francis sent a telegram to Chinese President Xi Jinping, following up an unprecedented message sent during his flight to South Korea on Thursday.
"Returning to Rome after my visit to Korea, I wish to renew to your excellency and your fellow citizens the assurance of my best wishes, as I invoke divine blessings upon your land," the pope's telegram said.
While it is tradition for the pope to send a message to countries he's flying over, the Vatican and Beijing have long had fraught relations, and Francis' predecessor, John Paul II, had to avoid Chinese airspace during an Asia trip.
On Sunday, Francis said Asian governments should not fear Christians, as they did not want to "come as conquerors" but be integral parts of local cultures. The remarks were intended for communist-ruled countries such as China, North Korea and Vietnam.
The Catholic Church in China is divided into an "official" Church known as the "Patriotic Association" answerable to the Communist Party, and an underground Church that swears allegiance only to the pope in Rome.
China's Foreign Ministry on Thursday said it had "noted" the pope's position, and repeated its position that Beijing was sincere about wanting to improve relations with the Vatican.
"We are willing to keep working hard with the Vatican to carry out constructive dialogue and push for the improvement of bilateral ties," the ministry said in a statement to Reuters. In its statement, it did not address the issue of Chinese barred from attending a youth event in South Korea.
About half of more than 100 Chinese who had planned to attend Sunday's Asian Youth Day event were unable to do so due to "a complicated situation inside China", an official with the local organiser of the pope's visit told reporters on Thursday.
'HONOUR AND HOPE'
One of the "comfort women" who sat in the front row at Monday's Mass, Kim Bok-dong, gave Francis a small butterfly-shaped pin that he wore on his vestment.
The pin is a symbol of their campaign, meant to convey that they want to be liberated and fly in a peaceful and free world, a non-profit group that supports the women said.
About 150,000 to 200,000 Korean women served as Japanese sex slaves, and most lived out their lives in silence; 56 are still alive, according to another nonprofit group.
The topic of comfort women has long been a thorn in relations between South Korea and Japan.
"That we could meet him was a big honour and hope," one of the women, Lee Yong-soo, a Catholic who is 87 and in a wheelchair, said after the Mass, showing off the white rosary Francis gave her. "Japan should take responsibility for what they did in the war. We were forced."
South Korea says Japan has not sufficiently atoned for the women's suffering, and has protested against Tokyo's review in June of a landmark 1993 apology, which said that the two countries had worked together on its sensitive wording.
Francis, met by festive crowds, spoke several times during his trip about inequality, which has been a theme of his papacy since being elected in March 2013.
South Korea is among the world's wealthiest countries, but is increasingly unequal, with nearly half its elderly living in poverty. South Korea has also seen rapid growth in the Catholic Church, which has doubled in the past 25 years to about 11 percent of the population of 50 million, adding some 100,000 new members each year. (Additional reporting by Philip Pullella; Editing by Michael Perry)