TOKYO, Sept. 28 (Xinhua) -- Japan's Newly-appointed transport minister Nariaki Nakayama handed in his resignation Sunday due to verbal blunders, the state broadcaster NHK reported, citing political sources.

Nakayama's resignation came only four days after he was appointed as land, infrastructure, transport and tourism minister in the cabinet of Prime Minister Taro Aso, who assumed the premiership and announced the lineup Wednesday.

On Friday Nakayama made some controversial remarks, calling Japan an "ethnically homogenous" nation, which drew bitter criticism from both ruling and opposition parties as well as the indigenous Ainu people.

On the same day, Nakayama also commented on those struggling for years against the building of the Narita airport, saying they are "more or less squeaky wheels" and their actions were a result of "bad postwar education."

The minister offered apologies for his verbal gaffes at a news conference later in the day amid angry protests from those who felt offended.