WASHINGTON (REUTERS) - US House Speaker John Boehner vowed on Sunday that Congress will avoid a government shutdown this week and he would push through as much unfinished legislation as possible before leaving at the end of October.

Speaking on CBS' Face the Nation two days after his surprise resignation, he said the House this week would pass a government funding bill now moving through the Senate, which does not meet conservatives' demands to cut off money for Planned Parenthood.

Asked if passage would require Democratic votes, he responded: "I'm sure it will, but I suspect my Democratic colleagues want to keep the government open as much as I do."

The Ohio Republican also announced that he would convene a special committee to investigate Planned Parenthood's abortion practices, similar to the one probing deadly attacks on US diplomatic faclities in Benghazi, Libya.

Mr Boehner resigned amid deep divisions among House Republicans over a range of issues including a Sept 30 deadline to approve new funding for federal agencies.

Conservative Republicans, some of whom have called for his ouster, have insisted on punishing Planned Parenthood by denying funds over allegations that the non-profit group improperly sold tissue harvested from aborted fetuses.

Planned Parenthood denies any wrongdoing.

Mr Boehner lashed out at the conservative groups and lawmakers who made his position untenable, including Senator Ted Cruz, the Republican presidential candidate. He said they "whip people into a frenzy" to make "unrealistic" demands.

"I mean, this whole idea that we were going to shut down the government to get rid of Obamacare in 2013, this plan never had a chance," he said.

Mr Boehner said he would try to clear as much of Congress' to-do-list as he could but did not name specific bills.

The Congress faces several important fiscal deadlines, including a transportation spending bill needed in October and a larger budget deal that would go beyond the 10-week extension to be passed next week.

An increase in the federal debt ceiling also will be needed by December and lawmakers from both parties want to revive the idled U.S. Export-Import Bank, which Boehner has long supported.

The speaker's resignation frees him to put legislation to House votes without fear of a move to oust him. "I expect that I might have a little more cooperation from some around town to get as much finished as possible," Mr Boehner said. "I don't want to leave my successor a dirty barn."