Prime Minister David Cameron has called Spain's newly elected leader Mariano Rajoy to congratulate him on his party's victory at the polls.
The centre-right Popular Party (Partido Popular) trounced the incumbent Socialists, securing 44% of the vote to their 29% share.
It has warned that Spain is "going to make all the sacrifices" to tackle the country's debts.
A Downing Street spokeswoman said: "The Prime Minister spoke to Mariano Rajoy at 9pm on Sunday night, congratulating him on the performance of the Partido Popular in the Spanish election, and on winning a crucial argument at a vital time for Spain and Europe.
"The Prime Minister said he looked forward to working closely with the new Spanish government.
"Rajoy said he followed UK policy closely and was keen to establish a close partnership with the Prime Minister."