Shigeru Ishiba, a former Japanese defence minister and leading candidate in the ruling party's leadership race, said there was "room to raise" corporate taxes, Kyodo News quoted him as saying late on Saturday.
"There are still firms that can bear the tax burden. I would like them to bear it a little more," Ishiba said in an election-related webcast, Kyodo reported.
Shinjiro Koizumi, a former Japanese environment minister who is also seen as a front-runner in the Liberal Democratic Party's leadership race, expressed his intention to introduce the creation of a carbon tax, the report said.
Koizumi said that if a carbon tax is not adopted, taxes will be levied on trade with Europe, where the tax is being introduced, Kyodo reported.
Sanae Takaichi, the minister in charge of economic security and another LDP leadership candidate, said she would oppose tax hikes for several years, the news agency reported.
"We should not raise taxes at all until we see a move towards price stability target, where demand exceeds supply," Kyodo quoted her as saying.
Japan's LDP, which has a parliamentary majority, will elect a new leader on Sept. 27, with the winner to replace outgoing Prime Minister Fumio Kishida.
(This story has been corrected to say Saturday, not Friday, in paragraph 1)
