Shadab Khan, the Pakistan allrounder, has signed for Lancashire for the remainder of the Vitality Blast, with Josh Philippe, the Australia wicketkeeper-batter, also joining Surrey for the same period.
Shadab, 27, is a replacement for Australian all-rounder Chris Green, who has been ruled out for the rest of the season through injury.
He has featured for Sussex and Yorkshire in previous Blast campaigns, and will be available for Lancashire's next match, against Leicestershire at Grace Road on Friday night.
"I am delighted to sign for Lancashire for the rest of the Vitality Blast," Shadab said. "I love playing cricket in England and have really enjoyed my previous stints in the competition.
"Lancashire is one of the biggest clubs in the country, with so much history, and I can't wait to pull on the shirt at Emirates Old Trafford in front of the home fans."
As one of the most experienced T20 players in world cricket, Shadab has represented Pakistan 124 times in the format, scoring 1,009 runs at a strike-rate of 144, alongside 123 wickets at 24 and an economy rate of 7.4.
Philippe, meanwhile, could also be in action on Friday, when Surrey take on Sussex, and will remain with the club if they reach the knockout stages.
Alec Stewart, Surrey's director of cricket, explained that the signing had been made in light of Will Jacks' and Sam Curran's England white-ball duties. "Josh Philippe is an excellent top-order batter to bring into the group ahead of Friday's match at Sussex," he added.
Philippe said: "The opportunity to join Surrey was a no-brainer for me. It's a massive club with some highly skilled players. I want to help the group push for the latter stages of the Vitality Blast.
"The Kia Oval is one of the great grounds in world cricket, so to be based there for a month will be awesome."