The further text says the following:

ULTIMATUM – The British government gave the USSR a brutal ultimatum.

In the name of keeping the peace, the USSR was forced to make serious concessions.

Strengthen the armed forces of the Soviet Republic, then we will put an end to the commitments made to the imperialists.

Build a Red Air Fleet - the most promising weapon of future wars.

In memory of the English Ultimatum and in memory of our common duty to strengthen the armed forces of the USSR, the ODVF calls on all citizens to form a fighter squadron with "Ultimatum" aircraft. Buy ODVF tokens for the aircraft of this squadron!