The association representing bookmakers in Northern Ireland says it is seeking "urgent confirmation" about when its members' shops can reopen.
Betting shops in the Republic of Ireland and England can trade again.
But the Stormont Executive's list of retailers that must remain closed in NI includes betting shops.
The decision is "forcing an initial 1,000 employees to remain on furlough", said the NI Turf Guardians' Association.
It represents the majority of betting shops trading in Northern Ireland, of which there are about 300, with 1,500 staff employed.
A spokesperson for the association said retail bookmakers had been preparing to reopen this week, after the executive gave the green light for all non-essential retailers in NI to reopen last Thursday.
"The local industry remains overwhelmingly dominated by traditional over-the-counter betting and the sustainability of the sector is dependent on the opportunity to resume business as soon as possible," they added.
The association said if NI bookmakers are not afforded the opportunity to compete with online gambling portals, it would place at risk the security of about 500 more jobs within betting shops.
Many betting shops in NI have "heavily invested" in redesigning shop layouts to ensure social distancing is maintained, the association said.
"Hand sanitation facilities, increased cleaning of surfaces and machines after customer use, and screening at payment points will also be place for the protection of customers and staff," they said.
The Department for Communities, which oversees gambling and betting shops in NI, has been approached for comment.