Sinisterra has already agreed on personal terms with Leeds and has been waiting for the two clubs to thrash out an agreement.
Leeds have been making progress in negotiations with Feyenoord and are close to securing a deal to sign the Colombian winger.
An agreement is close between the two clubs as they thrash out the final details of the deal for Sinisterra.
According to Dutch outlet 1908.nl, Leeds have agreed to pay a guaranteed fee of €25m and will pay another €5m in add-ons based on his performances.
Feyenoord have also managed to convince Leeds to include a sell-on clause as part of the agreement.
Should Sinisterra move on to bigger things from Leeds in the future, the Dutch would have their coffers filled up as well.
The two clubs are finalising the terms and Leeds are expecting to secure his signature this week.
Leeds are also on the cusp of signing American midfielder Tyler Adams from German club RB Leipzig.
