On 13 January 2014 the White House press office issued this press release (my emphasis):
Remarks by President Obama and President Rajoy of Spain After Bilateral Meeting
PRESIDENT OBAMA: Let me say it’s a great pleasure to welcome my friend, Prime Minister Rajoy, to the Oval Office … I should note that the World Cup is coming up. Spain is the defending titleholder, but the United States is rapidly improving -- (laughter) -- and so perhaps if the Prime Minister has some advice for us in terms of how we can win a title at some point, it would be most welcoming.
But thank you so much for the visit.
PRESIDENT RAJOY: (As interpreted.) Good afternoon. I will be giving you that advice so that you can come in second at the World Cup, and I’m sure you will understand why. (Laughter.)
Obama’s speech is correct and the titling is wrong; Rajoy is the Spanish prime minister. So where has this confusion come from?
The head of the Spanish government has the title in Spanish of presidente del gobierno, which can be translated as president of the government. He presides over meetings of the government, and the Spanish gobierno corresponds to the British cabinet (the British government includes a number of junior ministers who are not in the cabinet). It is the committee of about 20 ministers who have the highest executive authority in the country and are members of, and are responsible to, the country’s parliament as is usual in the European system. His constitutional position corresponds exactly to that of David Cameron as the British prime minister or that of Angela Merkel in Germany, where this position is called Kanzler (chancellor).
The problem arises from the Spanish word presidente, which does of course mean president in English in the sense of a head of state of a republic, both as an executive president like US Barack Obama and as a figurehead president like President Joachim Gauck of Germany. However, it also corresponds to the English chairman. The presidente of a chess club or of a residents’ association would be called in English the chairman, or increasingly the chair, of that organisation. So, far from, being the Spanish president Mariano Rajoy is, I would say as a literal translation, the chairman of the Spanish cabinet, although the website of his own office calls him the President of the Government of Spain. Certain confusion is understandable but the White House should be able to get it right. Rajoy is clearly not the president of the country; Spain does after all have a king as head of state.
In Catalonia, however, there is a more complex situation. Artur Mas is in Catalan the President de la Generalitat. In fact, his position is similar to that of any prime minister. He is a member of the Catalan parliament and is responsible to it, and he chairs meetings of the Catalan govern, which like the Spanish gobierno is the committee of ministers, i.e. the cabinet. The linguistic problem arises because the Generalitat is more than just the cabinet or government; the name refers to all the public authority under the Catalan government, what would be called the state apparatus in a sovereign state. Normally, that doesn’t matter (government is often used in Britain to describe what is really the state) but in translating Mas’s title there is a problem: although his constitutional position is equivalent to any prime minister, his title refers to the Generalitat, which is more than just the cabinet or government. The Catalan government refers to him in English as the President of the Generalitat. Nevertheless, his constitutional position is clearly that of prime minister and, as it seems paradoxical to have a president in the English sense of a word as the head of a level of government that is subordinate to the state, it would seem reasonable for a translator to use prime minister to describe the head of the Catalan government in English, or perhaps first minister, which is the title of the head of the Scottish government, or premier, which is used for the heads of the governments in the states of Canada and Australia. I must say, however, that most English-language media follow the Catalan government’s style.
The president of the Spanish region of Catalonia (BBC)
Catalonia's president, Artur Mas; The Catalan president (BBC)
THE president of Spain’s powerful northeastern region of Catalonia (The Scotsman)
The president of the north-eastern Spanish region of Catalonia Artur Mas (Reuters)
Catalonia's president Artur Mas (picture caption); Catalan President, Artur Mas; Spain's prime minister (The Guardian)
regional President Artur Mas; Spanish Prime Minister Mariano Rajoy (Bloomberg)
However, there is
The First Minister of Catalonia, Artur Mas (The Spain Report)
Artur Mas, president of Catalonia's regional government (Wall Street Journal). This is in a picture caption. The body text has: The leader of the Catalonia region and Catalan leader Artur Mas.