Britain should take a tougher stand towards Spain in disputes over Gibraltar, including using legal action and more diplomatic protests, a parliamentary committee urged on Tuesday.

Spain disputes British sovereignty over the peninsula, which has long been a point of contention in relations between the two countries, with tensions increasing over the last year.

Spanish police on Monday arrested a teenager suspected of beating up a Mongolian man inside a Barcelona metro train in an alleged racist attack after a video of the incident posted online went viral.

The 56-second video shows a blonde youth, dressed in a black T-shirt and jeans and whose face is pixelated, repeatedly punching the seated man before other passengers intervened late on Saturday.

Spanish activists on Monday removed part of a controversial artificial reef which was built in disputed waters near Gibraltar despite objections from Madrid.

The two-tonne concrete block was one of 70 that Gibraltar dropped into the sea in July 2013 saying it was creating an artificial reef that would boost fish populations.

Pope Francis received the new King of Spain Felipe VI and his glamorous ex-newsreader wife Queen Letizia at the Vatican on Monday, on their first foreign trip since taking the throne.

Felipe, 46, who was sworn in two weeks ago, invited the Argentine pontiff to Spain during what the Vatican described as "cordial discussions" between the heads of state.

Spain's new King Felipe VI reached out on Thursday to Catalonia, urging "collaboration" in the region where an independence drive has raised tensions with Madrid.

Amid high expectations on his first domestic trip since he took the throne a week ago, the 46-year-old offered a soothing message in one of the country's most politically sensitive regions.

Spanish lawmakers Thursday approved controversial new legal protections for ex-king Juan Carlos, who lost his total immunity when he quit the throne.

Juan Carlos left himself open to possible court action, including a paternity suit brought by a man claiming to be his son, when he gave up the throne last week after 39 years for his heir, King Felipe VI.

A public prosecutor on Thursday appealed against fraud charges that could bring Spanish King Felipe's sister Cristina to trial, accusing a judge of pursuing her on "mere suspicions".

Just a week after Felipe became Spain's new king, an investigating judge on Wednesday brought the 49-year-old princess a step closer to trial by upholding tax fraud and money-laundering charges against her.

A Spanish judge ruled Wednesday that King Felipe VI's sister, Princess Cristina and her husband should face fraud charges, opening the way to an unprecedented criminal trial.

Six days after Felipe, 46, took the Spanish throne promising an "honest and transparent" monarchy, the decision refocused attention on a scandal that had blighted the reign of his 76-year-old father Juan Carlos.

Dethroned champions Spain bowed out of the World Cup with a 3-0 win over Australia thanks to goals from David Villa, Fernando Torres and Juan Mata in Curitiba on Monday.

Villa, who is next set for a three-month spell in Australia with Melbourne City, became the fourth Spanish player to score in three World Cups when he backheeled home Juanfran's cross for his 59th international goal in his 97th and final appearance for La Roja nine minutes before half-time.

Madrid's top art museum the Prado unveiled a major show Monday about the master painter El Greco, exploring his influence on modern greats such as Francis Bacon and Jackson Pollock.

"El Greco and Modern Painting" is part of a year-long series of big exhibitions to mark the 400th anniversary of the Greek-born master's death.