UPDATE 1-U.S. oil export ban 'very likely' to be lifted in spending bill-source

(Adds background, remaining hurdles for bill)
WASHINGTON, Dec 11 (Reuters) - The 40-year-old ban on most
U.S. crude oil exports will "very likely" be lifted in the
government spending bill, and talks on the final budget deal are
likely to continue through the weekend, a Senate aide said on
Friday.
The aide did not want to be identified due to the ongoing
nature of the talks.
When asked if it was likely that the oil export ban would be
lifted, a spokeswoman for Senate Minority Leader Harry Reid, a
Nevada Democrat, said there was no final deal yet.
"We do not have a final agreement on the omnibus or tax
extenders," said Reid's spokeswoman Kristen Orthman.
Leaders in both the House and Senate have been meeting
behind closed doors in recent days to see if a deal can be
reached on the bill. Energy interests, and Republicans, who lead
both chambers of Congress, say lifting the trade restriction
would keep the U.S. drilling boom alive and give U.S. allies
alternatives to Russia and OPEC for their oil supplies.
Opponents, including many Democrats in the Senate, say it
would put oil refining and ship building jobs at risk and more
drilling would harm the environment and increase the number of
trains carrying crude oil.
The White House has said repeatedly that President Barack
Obama opposes legislation in the bill to lift the ban and that
Congress should instead work to help green sources of energy. It
has stopped short of saying Obama would veto a spending bill
that includes lifting the ban.
The Senate aide said Democrats were very likely willing to
trade lifting the ban for a multi-year extension of wind and
solar tax credits and reauthorization and full funding of the
Land and Water Conservation Fund, which maintains national parks
with revenues from oil operations.
There were still major disagreements over the funding bill
ahead of a deadline on Wednesday on the $1.15 trillion package
to fund the government through September, 2016. Many of the
disagreements are related to Congress' response to the recent
gun massacres in Paris and California.
On energy matters in the bill, Democrats oppose efforts to
block emissions rules by the Environmental Protection Agency or
U.S. funding of the UN Green Climate Fund, a major item that is
part of ongoing climate talks in Paris.