Apple CEO Steve Jobs made a surprise appearance at a Cupertino City Council meeting late Tuesday to announce plans for a major expansion.

``Apple is growing like a weed,'' Jobs told the council, adding that space restrictions at the company's existing Cupertino headquarters have forced it to rent space in smaller buildings scattered throughout the city, located about nine miles west of San Jose.

Jobs presented renderings of a proposed 150-acre (60-hectare) campus built around a gigantic circular building made almost entirely of curved glass, with a heavily landscaped center.

``It's a little like a spaceship landing,'' he said of the futuristic design.

Jobs also highlighted environmentally friendly touches such as a natural-gas-fired energy center that would serve as the site's main power source. Most of the parking would be underground, creating space for thousands of additional trees on the property, he said.

Apple purchased most of the land from Hewlett-Packard Co., which plans to move out by next year.

The new site would allow Apple to increase its workforce and consolidate far-flung staff in one location, Jobs said. He said the iPhone and iPod maker also would continue to use its existing headquarters, which accommodates about 2,600 employees.

City officials appeared enthusiastic about the planned expansion.

``Now that we've seen your plans, the word `spectacular' would be an understatement,'' Councilman Orrin Mahoney said. ``And I think everyone is going to appreciate what clearly is going to be the most elegant headquarters _ at least in the U.S. _ that I've seen.''

Asked how the expansion would benefit Cupertino, Jobs noted that Apple is already the city's largest taxpayer. If the company cannot continue to expand within city limits, it will be forced to move elsewhere, he said.

City leaders were quick to discourage that prospect.

``Apple is truly a technology of innovation, and our city staff and City Council looks forward to working with you and helping you succeed here in our community,'' Mayor Gilbert Wong said after pulling out his Apple tablet computer, an iPad 2, to show Jobs.

Jobs said he hoped to submit formal plans for the new campus ``fairly quickly,'' with the goal of breaking ground next year and moving into the space by 2015.

Jobs' appearance at the council meeting, which elicited gasps and excited murmurs from the crowd, came one day after he gave the keynote address at a conference for application developers in San Francisco.

The 56-year-old has been on medical leave for the past five months _ his third in the past seven years _ to deal with an unspecified medical issue. He has previously survived pancreatic cancer and undergone a liver transplant.