Japanese Prime Minister Shinzo Abe has apologised to his party for causing anxiety and loss of confidence in his government.

Abe's ratings have collapsed amid allegations of cronyism and an attempt to cover up the scandal. He told his ruling party's annual convention on Sunday that as the head of government he feels responsible for the scandal involving the sale of state-owned land at a huge discount to a nationalist school operator with ties to his wife. The Liberal Democratic Party convention approved a proposal to revise Japan's pacifist constitution in line with a plan floated by Abe last year to explicitly refer to Japan's military.