Ibrox side Glasgow Rangers are on the hunt for two more additions this summer.
Rangers are hoping to sign two new players - believed to be a striker and a centre-back - before the competitive campaign begins.
However, Warburton admits that he is still isn’t certain whether either of Rangers' transfer targets will be signed up on loan or permanent deals.
“We are looking at two more now, whether they are permanent or loans is to still be decided, we would hope permanent,” Warburton said.
“Two more would be perfect and I am delighted with the work from Frank and his team and the club in general.
“You have to try and get your work done early and discreetly as possible, under the radar, if you can do that.
“We want the best value for Rangers and hopefully that will be the case.”
Rangers have wasted no time strengthening their squad, following their promotion to the Scottish Premiership.
Rangers have already made eight new additions this summer, and they have been one of the most active teams in Scotland.
The Glasgow side managed to earn promotion with a thin first-team squad, but Warburton has been keen to add depth following their return to the top tier.
Rangers have brought in a large amount of experience, while also targeting the best players from the Football League.
Warburton has suggested that both his targets are yet to be linked with Rangers in the press lately.