TOKYO (Kyodo) -- A survey of new condominium transactions in major metropolitan areas showed a rise in buyers with overseas addresses, with Tokyo seeing the share double to 3.0 percent in the January-June period of 2025, the land ministry said.

Speculative purchases that drive up prices without actual demand are believed to exist, analysts said, prompting the government of Prime Minister Sanae Takaichi to consider countermeasures regardless of whether buyer addresses are in Japan or abroad.

When limited to the six central Tokyo wards, including Chiyoda, which hosts the Imperial Palace, many government offices and leading businesses, the share rose from 3.2 percent to 7.5 percent, underscoring a surge in purchases linked to overseas addresses.

The majority of buyers were registered in Taiwan, followed by those in China, Singapore, Hong Kong and Britain.

Land minister Yasushi Kaneko acknowledged that the Japanese government does not have data on the nationalities of buyers, but said at a press conference on Tuesday, "Speculative transactions not based on actual demand are undesirable."

He said the ministry will work with the real estate industry to curb such activity, with a source close to the matter saying Japan is considering a system that would require property transfer registration applicants to disclose their nationality.

Outside Tokyo, Sapporo in northernmost Hokkaido recorded a near-tripling of its share, climbing from 0.7 percent to 2.0 percent. The figure in Kanagawa Prefecture, which borders Japan's capital, also grew from 0.3 percent to 1.0 percent.

The survey was conducted by the Ministry of Land, Infrastructure, Transport and Tourism for the first time amid concerns that speculative purchases by foreign buyers are driving up condominium prices.

As nationality is not recorded in property registry data, the ministry identified buyers by the addresses listed in those records.

Some have expressed concerns about how listing nationalities in the data may be used, with a Justice Ministry official noting that it could be singled out and "lead to discrimination or human rights violations."

The government is considering requiring details of nationality, but will likely keep the information for its own use rather than disclose it in property registry data, the source said.

Takaichi, who took office on Oct. 21, has pledged to introduce stricter rules on land acquisition by nonresident foreigners, as she has pursued policies shaped by her conservative and hawkish views on defense and economic security.