* Afghan spokesman rejects deadline, says assembly to decide
* Most elders at assembly appear to favour accord
* Failure could prompt pullout of U.S. forces after 2014 (Adds comment from White House, Hagel, paragraphs 6-7, 9-10)
By Jessica Donati and Hamid Shalizi
KABUL, Nov 22 (Reuters) - The future of U.S. troops in Afghanistan remained in doubt on Friday after a spokesman for President Hamid Karzai rejected a U.S. call to sign a security pact by the end of the year rather than after next year's presidential election.
The United States has repeatedly said it will not wait until after the April 2014 vote to seal the Bilateral Security Agreement (BSA) and rejected Karzai's suggestion for the signing to take place next year "properly and with dignity".
Without an accord, the United States could pull out most of its troops by the end of 2014, as it did two years ago when it failed to negotiate a deal with Iraq.
"We do not recognise any deadline from the U.S. side," said Aimal Faizi, a spokesman for Karzai, as Afghan tribal elders considered the pact for a second day. "They have set other deadlines also, so this is nothing new to us."
Karzai had suggested on Thursday, as the Afghan leaders began a meeting known as a Loya Jirga, that the signing of the pact should wait until after the poll. Having served two terms, he is ineligible to run again.
In Washington, the White House kept up the pressure on Karzai, saying President Barack Obama wanted the BSA signed by the end of the year. Obama would decide about a further U.S. presence after Afghan authorities approved the deal, U.S. officials say.
"It is our final offer," said White House spokesman Jay Carney.
"We can't push it into next year and be expected to plan for a post-2014 military presence," he told reporters.
U.S. Defense Secretary Chuck Hagel said the United States need to ensure there would be protection for U.S. forces if the United States kept troops in Afghanistan beyond next year.
"Without that, I, as secretary of defense, could not recommend to the president of the United States to go forward," he said on a visit to Halifax.
U.S. Secretary of State John Kerry said this week the language of the accord had been agreed.
Faizi refused all comment on whether Karzai endorsed the plan. He said any action by the president depended strictly on the recommendation of the Loya Jirga.
"It is absolutely up to the Jirga to decide about the BSA. The president very clearly said good security, peace and good elections are the key to the signing of this document."
Most participants at the gathering's second day appeared to favour ratifying the pact. But reporters had little access to opponents of the deal and were kept away by security staff.
"We have to sign this agreement with the United States of America," said Aminullah Mawiz Nooristani, an elder from eastern Nuristan province. "President Karzai has to sign it as soon as we announce our decision."
Afghanistan has wrangled for more than a year over the pact with the United States, which has had troops in the country since the Taliban was ousted from power late in 2001.
Karzai has had an increasingly fraught relationship with Washington and is reluctant to be associated with the pact.
"My trust with America is not good," Karzai told the assembly on Thursday in his opening speech. "I don't trust them and they don't trust me."
The elders, largely handpicked by Karzai's administration, are expected to vote in favour of the document and urge the president to follow their advice, allowing Karzai to distance himself from the process without jeopardising the deal.
The 2,500-member assembly is expected to announce its decision on Sunday.
The pact contains painful concessions such as immunity for U.S. forces from Afghan law and allowing them to enter Afghan homes if an American life is under direct threat.
"Whatever the Jirga tells him, whether they tell him to sign it before election or after the election, he will follow through," said Hasseeb Humayun, a member of the group.
If the United States pulls out its troops, other countries in the NATO alliance underpinning Karzai's administration are expected to follow suit and a thinner international presence could deter donors from releasing promised funds.
Afghanistan remains largely dependent on foreign aid. (Additional reporting by Mirwais Harooni and Abdul Aziz Ibrahimi, Steve Holland and Jeff Mason in Washington, and Phil Stewart in Halifax; Editing by Maria Golovnina, Ron Popeski, Clarence Fernandez and Eric Walsh)