Wagamama owner TRG said it would pay £7.5 million (€8.75 million) to private equity-backed Big Table as part of the deal, which includes 75 sites and restaurants. The buyer will pay TRG a nominal value of 1 pound.
TRG shares were up 6% to 50 pence by 0703 GMT.
The company over the past year has struggled with financial losses and last week said Chairman Ken Hanna would step down after months of pressure from activist investors to change its management and improve profitability.
"The Board is continuing to actively explore its strategic options to further accelerate margin accretion and deleveraging," it said.
The divestment means that TRG would focus on three divisions - Wagamama, Pubs and Concessions, the group said.
"We ...believe that divesting the Concessions business could be a neat way to assuage debt concerns without diluting the quality of group earnings," Stifel analysts said.
Big Table Group
Its Concessions business, trading mainly in UK airports, has more than 40 sites, including bars, restaurants and sandwich shops.
Big Table Group operates more than 160 sites across the UK, with restaurant brands including Bella Italia and Las Iguanas.
The deal is expected to close in the fourth quarter, and will likely add to earnings in the first full year after completion, TRG said.
Frankie And Benny’s
In March, TRG said it would shut 30% of its Frankie & Benny's and Chiquito restaurants after it posted an annual loss.
The responsibility of the closed sites will remain with TRG, it said on Monday.
Frankie and Benny’s was founded when the company opened its first restaurant in Leicester in 1995. TRG bought Mexican food chain Chi Chi and rebranded it Chiquito in 1989.