Britain was a driver towards Israeli independence; it was also a major actor preventing it. They sorta had it both ways.

In the '20s Britain committed to creating a Jewish state in Palestine. However, it also committed to some sort of Arab confederation in the same area. So while it was initially acting in the interests of the nascent Jewish statehood movement, it was conflicted from the beginning.

Over time, the relationships got more strained. A series of Jewish-Arab violent incidents made the British want to put the brakes on everything, leading to restrictions on Jewish immigration. This was during the 1920s and 1930s, and meant that Jews trying to escape Europe couldn't. In the minds of Jewish groups in Palestine, the British were now an obstacle towards statehood. What followed was a campaign of illegal Jewish immigration, and an escalating conflict between the Jewish paramilitaries and the British.

After WW2, this reached a fever pitch. International pressure was on the side of creating a Jewish state, in no small part because of thousands of Jewish Holocaust survivors who couldn't immigrate to Palestine because of British restrictions. But the British held their position, and the conflict escalated. It was quite violent. The most famous example was the bombing of the King David Hotel, where the Mandatory Government had offices. But attacks on British soldiers and infrastructure were commonplace.

In the 1947 UN vote to partition Palestine, the UK abstained. And when the vote passed, they sort of gave up on governing, and did a half-assed handover to the Jewish Agency in some cases. Relations improved during the '50s, but they began quite coldly after independence.