Wrong.
The country of Palestine was created by the Treaty of San Remo in 1920.
{...
The
San Remo conference was an international meeting of the post-
World War I Allied Supreme Council as an outgrowth of the
Paris Peace Conference, held at
Castle Devachan in
Sanremo, Italy, from 19 to 26 April 1920. The
San Remo Resolution passed on 25 April 1920 determined the allocation of Class "A"
League of Nations mandates for the administration of three then-undefined
Ottoman territories in the
Middle East: "
Palestine", "
Syria" and "
Mesopotamia".
...
Asserting that not all parts of the Middle East were ready for full independence, mandates were established for the government of three territories: Syria, Mesopotamia and Palestine. In each case, one of the Allied Powers was assigned to implement the mandate until the territories in question could "stand alone." Great Britain and France agreed to recognize the provisional independence of Syria and Mesopotamia, while claiming mandates for their administration. Palestine was included within the Ottoman administrative districts of the
Mutasarrifate of Jerusalem together with the
Sanjak of Nablus and
Sanjak of Akka (Acre).
[8][9][10]
The decisions of the San Remo conference confirmed the mandate allocations of the Conference of London. The San Remo Resolution adopted on 25 April 1920 incorporated the
Balfour Declaration of 1917. It and Article 22 of the
Covenant of the League of Nations were the basic documents upon which the
British Mandate for Palestine was constructed. Under the Balfour Declaration, the British government had undertaken to favour the establishment of a national home for the Jewish people in Palestine without prejudice to the civil and religious rights of existing non-Jewish communities in Palestine or the rights and political status enjoyed by Jews in any other country.
[11]
...
It was agreed –
(a) To accept the terms of the Mandates Article as given below with reference to Palestine, on the understanding that there was inserted in the
procès-verbal an undertaking by the Mandatory Power that this would not involve the surrender of the rights hitherto enjoyed by the non-Jewish communities in Palestine;
...}