Trading on Madrid's stock exchange resumed Monday after a five-hour blackout that was blamed on a technical problem.
The benchmark Ibex 35, which has been hugely volatile this year due to concerns about Spain's financial crisis, rose when trading began again, just before 3 p.m. (1300 GMT). It closed the day 4.4 percent higher.
The breakdown didn't have major consequences, said Ramon Zarate, who heads a Madrid financial analysis company.
"The market came back and has been on a strong upward curve," he said.
The Ibex lists major global companies like Inditex, the owner of the Zara clothing retailer, as well as banking group Santander and telecoms operator Telefonica.
Exchange spokesman Jesus Merino said technical problems had caused the breakdown in trading but he could give no further details.
Spain's stock market has mostly risen in the past week on hopes after the European Central Bank chief, Mario Draghi, said his bank was working on a plan to help lower borrowing rates for indebted countries like Spain.
The government is desperate to avoid having to seek a sovereign financial bailout but its problems are mounting. Debt is rising due to the cost of rescuing ailing banks and regional governments, while the economy is in recession and unemployment is near 25 percent.
The economic troubles of Spain and the wider 17-nation eurozone were among the topics discussed by Spanish Prime Minister Mariano Rajoy and U.S. President Barack Obama during a 30-minute call on Monday, Rajoy's office said in a statement.
Rajoy told Obama about Spain's efforts to reduce the government deficit and the series of budget cuts that his administration has pushed through since the beginning of this year.