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Mayor Gavin Newsom during a news conference Sept. 2, 2010 in San Francisco

San Francisco Mayor Gavin Newsom directed his top officials to suggest budget cuts of 20 percent in each of their departments before he leaves office next month.

Newsom told city brass during a meeting on Wednesday that a budget gap of $380 million is anticipated next fiscal year, which begins in seven months.

That shortfall, which is lower than the $712 million deficit projected in April by budget analysts, represents roughly 10 percent of the general fund’s annual income, which has fallen dramatically in recent years.

Tax revenues are expected to increase next fiscal year, but those gains will be offset by reductions in state and federal payments, Newsom told department heads. The shortfall projection assumes that $16.7 million can be withdrawn from a rainy-day fund.

Newsom directed the department chiefs to provide him with recommendations by Dec. 21 for reducing their budgets by 10 percent, plus an additional 10 percent in contingency cuts.

At least 2.5 percent in savings must be suggested for this fiscal year.

Newsom is scheduled to begin a new job as the state's lieutenant governor next month.

“The mayor reaffirmed his commitment to further reduce next year's deficit before he leaves office and leave a blueprint for a balanced budget and list of alternatives in place for the interim mayor,” spokesman Tony Winnicker said.