Winger Goneva, 35, is 14th on the list of all-time top league scorers in England with 58 tries, and at international level has 20 in 55 Tests.

Meanwhile, Cavubati, 31, made eight Premiership appearances last season.

The lock will arrive once Fiji's World Cup commitments are completed in Japan this autumn.

"Big Tex is an excellent signing for the club and I am delighted he is joining us for the new season," said head of rugby Paul Gustard. "I have been looking to add a lock for some time and when Tevita's name was proposed he was a standout candidate for us."

Cavubati's team-mate Goneva spent five years at Leicester Tigers before joining Falcons in 2016, and offers a replacement for the retired Tim Visser.

"It's a real coup for us," added Gustard. "With Tim's retirement at the end of last season we have been looking to bring in quality to supplement our very exciting young wingers in Gabs [Ibitoye] and Cadan [Murley], and there is no doubt Niki is real quality."

The duo join another new import in Springbok three-quarter Travis Ismaiel at The Stoop for the forthcoming campaign.

"They were the first club that I had a jersey for," said Goneva. "My dad bought me one when I was very little because it is his favourite team, and so I have always had an affinity for them."