In a speech Saturday, Ali abdullah Saleh lashed out at so-called "world super powers" and his Arab Gulf neighbors, who he accuses of funneling cash to protesters challenging his rule.
"To the Americans and Europeans, al Qaeda is coming and it will take control," he said, addressing members of the security forces on the anniversary of a 1990 deal he oversaw that united north and south Yemen. "The future will be worse than the present."
Still, Saleh said he will sign the deal to leave office. It gives him immunity from prosecution if he steps down within 30 days.
Saleh has clung to power despite more than three months of daily protests and defections by military commanders and other allies.
The United States, which had supported Saleh with financial aid and military equipment to fight the country's dangerous al Qaeda branch, has backed away from the embattled leader.
The Associated Press contributed to this report.