Regional Madrid head's resignation piles pressure on ruling PP

MADRID (Reuters) - The head of the region of Madrid, Cristina Cifuentes, resigned on Wednesday after claims she had falsified her master's degree and been caught shoplifting in 2011, the latest blow to the ruling People's Party (PP) ahead of regional elections next year.

Madrid is traditionally a stronghold for Prime Minister Mariano Rajoy's centre-right party but is under growing pressure from market-friendly Ciudadanos, which is polling ahead as the PP struggles with corruption scandals and the Catalonia political crisis.

A close circuit TV video published by newspaper OK Diario on Wednesday showed Cifuentes emptying her handbag for a security guard in a supermarket after being accused of taking anti-aging cream.

Cifuentes, 53, before tending her resignation, said taking the cream, worth around 40 euros, had been an "involuntarily error". She was released after paying for the cream.

"I have made many mistakes, I will continue to make more but my whole life is being questioned with a certain intention," Cifuentes said during a news conference on Wednesday.

The master's degree scandal broke out last month when eldiario.es, a news website, reported a string of alleged irregularities in Cifuentes' graduate degree in public law.

The website accused her of having done no course work or sat any exams. Cifuentes denied wrongdoing or preferential treatment, threatened to sue the site and released a copy of a university document.

Her resignation is a setback for the PP because she was seen by many as a potential future leader of the party as a member of a different generation untarnished by past corruption, and was expected to run in next year's elections.

Cifuentes headed the region of Madrid since 2015 thanks to the support of Ciudadanos, which had also threatened to join a motion of confidence to force her resignation after the master's scandal broke.

Ciudadanos strict stance against the Catalonia independence movement, which has pushed the government in to its worst political crisis in decades, has helped lift the relatively new party to head voting intention polls.

(Reporting by Paul Day and Jesús Aguado; editing by Jesús Aguado and Angus MacSwan)