The foreign minister of Japan, Seiji Maehara, has resigned his office after revelations emerged that he accepted a political donation from a foreign source (which is illegal according to Japanese law).

Maehara admitted he took a 50,000 yen ($610) donation per year between 2005 and 2008 and again in 2010. from a South Korean citizen resident in Japan.

(Thousands of South Korean nationals live in Japan, although many have not received Japanese citizenship).

The opposition had urged Maehara to quit. The law was put in place to prevent foreigners from having any influence in domestic affairs.

I apologize to the Japanese people for stepping down after only six months and provoking distrust over a problem with my political funding, although I have sought to pursue a clean style of politics, Maehara said. “I apologize to the people for inviting mistrust over the relationship between money and politics,”

The resignation creates more problems from Prime Minister Naoto Kan, who is desperately seeking to pass a national budget through parliament, while trying to retain his own job.

Maehara was a key ally of Kan and was once viewed as a potential successor to the Prime Minister.

Kan is also trying to stave off demands by the opposition for an early election, as he seeks to implement tax reforms to tackle the costs related to Japan’s aging demographics and huge public debt.

On March 1, Japan’s lower house of parliament passed Kan’s 92.4-trillion yen budget, but the opposition refused to support his budget financing bills, which would require the approval of either the Upper House (which is dominated by the opposition) or a two-thirds majority in the Lower House, which Kan’s Democratic Party of Japan doesn’t have.

Due to this legislative impasse, Kan may be forced to dissolve the parliament and call a new election.