TOKYO - Support for the government of Japanese Prime Minister Fumio Kishida edged up in the wake of his ruling party's election win, but hurdles remain for key parts of his agenda, including constitutional revision, according to opinion polls.

Kishida's ruling Liberal Democratic Party (LDP) increased its seats held in the upper house of parliament in Sunday's election, and maintained a majority with its conservative coalition in the poll, conducted two days after former prime minister Shinzo Abe was killed at a campaign rally.

Support for Kishida's government rose to 65% in a poll by the Yomiuri Shimbun, up 8 points from a late June survey, while a different poll by Kyodo News Agency pegged support at 63.2%, up 6.3 points.

Both polls were conducted on Monday and Tuesday.

A vast majority of voters polled by the Yomiuri, 79%, want Kishida to stay in office for at least two years, or around the time of the next election for president of the LDP, who by virtue of his party's majority becomes prime minister.

Of that, 27% wanted him as prime minister for "as long as possible."

But this support doesn't necessarily translate into support for Kishida's agenda, including revising the pacifist constitution - something that Abe had wanted to do.

Only 37% of voters polled by Kyodo thought the issue should be handled "speedily," while 58.4% believed there's no need for haste.

(Reporting by Elaine Lies; Editing by Simon Cameron-Moore)