What treaty was signed between the british and spanish?

Hello there!

There were several treaties that were signed by the British and Spain.

The treaty of Versailles was signed by the British and Spanish.

I hope this is the answer you were looking for! 

The Spanish government again reasserted their sovereignty of Belize in subsequent treaties of 1783 and 1786. In the Treaty of Versailles, which was signed by the British and Spanish governments, the concessions given by Spain to Britain to cut logwood were defined more precisely than in the Treaty of 1763.