Barbara Woodward, director general of economic and consular affairs at the Foreign and Commonwealth Office, made the comments during a question and answer session at Civil Service Live.
Her comments come in the wake of a statement by prime minister David Cameron, who said that he would consider the possibility of holding an ‘in-out’ referendum after the next general election.
But Woodward said: “I think our membership of the European Union is really important to our place in the world economy and the multilateral framework.
“A lot of companies locate in the UK because it is a springboard to European markets for them.”
David Frost, director for Europe, trade and international affairs at the Department for Business, Innovation and Skills, added that the government must use the next 10-15 years to build relationships with emerging countries – some of whose economies could overtake the UK.
“There is a sense of urgency,” he said.