A group of downtown small businesses that managed to survive after September 11, 2001, are now seeking to survive their impending displacement by the Metropolitan Transportation Authority’s Fulton Street Transit Center and the powers of eminent domain.

Members of the Ground Zero Small Business Association, comprising 140 businesses and 700 workers, said yesterday at City Hall that the MTA’s offer to recoup the costs of relocation and improvements made to their work spaces does not constitute a fair deal.

A downtown retailer, Isaac Zafarani of Renaissance Jewelers, said, “When this eminent domain law was created, no one had experienced 9/11. Now they are offering to pay our moving costs. That’s embarrassing.”

The MTA will purchase at least six buildings to make way for the transit center, which is supposed to improve connections between 12 Lower Manhattan subway lines, at an expected cost of more than $750 million. Construction of the glass-and-steel design, touted as the “Grand Central of downtown,” is scheduled to begin next year, with completion in 2008.

The members of the Ground Zero Small Business Association, formed in June, are a diverse mix: street-level retail businesses and food services, social workers, a statistician, doctors, lawyers, tailors, jewelers, a psychotherapist, literary agents, graphic artists, and the city’s largest Polish language newspaper.

Under the eminent domain law, the tenants of the buildings to be condemned are not entitled to any compensation.

The chairman of the association, Arthur Castle, a statistician, said the group is seeking “affordable space downtown that is equivalent to what we are losing under eminent domain.”

Mr. Castle said there is limited space available that can accommodate small businesses in Lower Manhattan and that subsidies are necessary to convince landlords to subdivide large office spaces.

A spokesman for the MTA, Tom Kelly, said tenants would be paid for relocation expenses and the value added to the property. “Some of those people that were demonstrating have already agreed to a relocation cost. The rest we will be dealing with over the next week or two,” he said.

Mr. Kelly would not provide any details of the offers.

A spokesman for the New York City Department of Small Business Services, Benjamin Branham, said yesterday that the city plans to offer to assist the group of downtown businesses with relocation and finding alternative sources of financing.

Many of the tenants who spoke yesterday expressed a desire to stay near ground zero. A local retailer, Steven Mandel of Renaissance Jewelers, said his store, about a block from the site, has become a makeshift museum for tourists as they seek to learn about the events of September 11, 2001, and the aftermath. “I have an emotional connection to downtown,” he said.

A tailor who faces eviction, William Saad, said, “If I go further than four blocks, I’m ruined. I’m 52 years old, and I cannot start from scratch again.”

Some of the tenants received extended small-business loans and commercial tax breaks as incentives to remain in Lower Manhattan.

“We were asked to stay. Now that we are back on our feet, we are being asked to leave,” a graphic designer, Katherine Hill, said.