By Kaori Kaneko and Linda Sieg
TOKYO (Reuters) - Prime Minister Shinzo Abe's wife has cut ties with an elementary school involved in a land deal that provoked opposition questions just as the Japanese leader was basking in the glow of a friendly summit with U.S. President Donald Trump.
Abe has said neither he nor his wife, Akie, was involved in a murky deal for the purchase of state-owned land by Moritomo Gakuen, an educational body in the western city of Osaka that also runs a kindergarten promoting patriotism.
The affair has energized the often-floundering opposition, offering a reminder of the unexpected pitfalls that could still emerge for Abe's seemingly stable rule, now in its fifth year.
Abe, grilled about the purchase of the land at a rock-bottom price, said on Friday his wife would scrap a plan to become honorary principal of an elementary school the institution will open in April.
Last year, Moritomo Gakuen paid 134 million yen ($1.2 million), or 14 percent of the appraisal price, for an 8,770-sq-m (94,400-square-foot) plot on which to build the elementary school, official data show.
The difference reflects the cost of waste cleanup at the site, officials have said. Finance Minister Taro Aso told parliament this week there were no problems with the deal.
Abe said his wife had tried to refuse the role as honorary principal, and only accepted after it was announced to parents.
"Despite this, she decided that it would be detrimental for both the students and the parents if she continued, and so she told them she would resign," he added.
The institution's president, Yasunori Kagoike, heads the Osaka branch of Nippon Kaigi, or Japan Conference, a nationalist lobby group with close ties to Abe and his cabinet.
On the school's website, Akie had said: "I was impressed by Mr. Kagoike's passion for education and have assumed the post of honorary principal."
Abe said the comments were removed from the website on Thursday at his wife's request.
Abe reiterated that he had declined to let his name be used when Moritomo Gakuen sought donations for what it called the "Abe Shinzo Memorial Elementary School".
He has also denied that either he or his wife was involved in obtaining approval for the school, or in the land acquisition, saying last Friday that he would resign if evidence to the contrary were found.
The main opposition Democratic Party has seized on the affair. "The prime minister is talking as if he were the victim, but it is the people who should be angry," Democratic Party lawmaker Kiyomi Tsujimoto told reporters.
Abe returned to office in 2012 for a rare second term, promising to reboot the economy and bolster defense policies, after having abruptly quit in 2007, following a year marked by scandals in his cabinet, a big election loss and ill-health.
His cabinet this time has lost several ministers to money scandals, but Abe himself has been untainted by scandal.
Abe's approval rating rose five points to 66 percent in a media survey after his summit with Trump, where the leaders hugged, golfed and reaffirmed the U.S.-Japan alliance.
But his popularity could take a hit if the scandal continues to preoccupy the media, some political analysts said.
"The thing that makes a scandal really serious is when it keeps getting headlines," said Chuo University political science professor Steven Reed.
(Additional writing by Elaine Lies; Additional reporting by Kiyoshi Takenaka; Editing by Clarence Fernandez)