The fashion chains join a list of more than 40 retailers to have agreed deals at the£400 million development.
Tenants include anchor House of Fraser, fashion stores Reiss, Cruise, All Saints, Ted Baker, Urban Outfitters and furniture retailer Habitat.
The Fossil store will be the first in Northern Ireland. The clothing and accessories brand, which primarily sells watches and jewellery, but also sunglasses, wallets, handbags and belts, has taken a 760 sq ft (70 sq m) unit on the upper ground level of Victoria Square.
French Connection will relocate from its existing store on Cornmarket to a 2,990 sq ft (280 sq m) store on the lower-ground level of Victoria Square.
The unit will be its largest franchise store in the UK and Ireland and will sit opposite Clockwork Orange and Tommy Hilfiger. It will showcase the entire French Connection lifestyle collection and create a further 20 jobs at the franchise company.
La Senza has also committed to increasing its offer in Belfast with a 2,385 sq ft (220 sq m) unit on the upper-ground level, between H&M and River Island.
Claire’s Accessories will occupy a 1,170 sq ft (110 sq m) store, also on the upper-ground level. It will be the third Claire’s Accessories in the city.
When Victoria Square opens in March, Belfast’s retail catchment is forecast to attract an annual retail expenditure of£828.9 million, according to market analysts CACI. This represents an overall uplift of 17.2 per cent.
In addition, Victoria Square is set to narrow the gap between Belfast and Dublin, with the market potential attracted to Belfast expected to close to less than 10 per cent behind Dublin.
The Victoria Square redevelopment is being hailed as one of Europe’s largest regeneration projects. It will include about 800,000 sq ft (74,320 sq m) of retail space covering three floors with 98 shops.
The development will also feature a cinema, restaurants, cafés and bars, as well as 106 apartments.