Greece would most likely take legal action against a "Grexit" in European court if its membership in euro zone is threatened, Greek Finance Minister Yanis Varoufakis said in an interview with the Daily Telegraph.

"We are taking advice and will certainly consider an injunction at the European Court of Justice. The EU treaties make no provision for eurozone exit and we refuse to accept it. Our membership is not negotiable," Varoufakis told the paper.

"The Greek government will make use of all our legal rights," he said in a press release issued by his office on Tuesday.

Since the Greek government decided on Saturday to hold a referendum on July 5 asking Greek voters to vote on a new bailout draft agreement with international creditors, the country stepped closer to a financial collapse that could lead to its exit from the eurozone, as foreign funding was cut off.

Greek banks have been shut and capital controls have been imposed since Monday.

The country faces a critical deadline on Tuesday. By the evening, Greece must pay back about 1.5 billion euros (1.67 billion U.S dollars) in loan installments to the International Monetary Fund.

Failure to meet its obligations for a second time in a month could set in motion the procedures to default in coming weeks.