London Irish have signed South African internationals Arno Botha and Piet van Zyl from South African franchise Blue Bulls with immediate effect.

Twice-capped back row Botha, 26, can play at either flanker of No. 8, and after starring at the 2011 Under 20s World Cup, was awarded a first Springbok call-up against Italy in 2013.

Speaking on his decision to try and boost Exiles' Aviva Premiership survival hopes, Botha said: “I’m delighted to have the opportunity to join London Irish, a club that is steeped in history and tradition.

“I’ve always wanted to test myself in northern hemisphere rugby and I’m really looking forward to the challenge of helping the club secure its Aviva Premiership status.”

Van Zyl, meanwhile, has three international appearances to his name and will provide competition to Scott Steele and Ben Meehan with Brendan McKibbin a long-term injury victim.

The 28-year-old made 76 appearances in Super Rugby, moving to the Bulls from the Cheetahs before his arrival in England.

He said: “I’ve heard a lot of good things about London Irish and I’m excited at the prospect of playing for the club in the Aviva Premiership.

“I wanted a fresh challenge and the opportunity to make the move to the northern hemisphere was too good to turn down.

“I’ll be doing everything I can to help the club move up the Aviva Premiership table and I can’t wait to pull on the famous green jersey.”

With London Irish 10 points adrift of Worcester in the Premiership table, a delighted Exiles’ director of rugby Nick Kennedy believes the double signing can give his side a real boost.

He said: “Arno is an aggressive ball carrier, who has the ability to consistently get over the gain line.

“From a young age Arno was tipped as a future Springbok captain, but injuries hampered his progress. However, he’s now back to full fitness and his injuries are very much behind him as he looks to make an immediate impact with us.”

He continued: “I’m very pleased to welcome Piet to London Irish and he brings a lot of experience to our back division.

“With Brendan’s injury, Piet’s arrival bolsters our scrum half options and I’m really looking forward to seeing what he can bring to the team in the coming weeks.”