Greece's finance minister says a copy of the country's original bailout agreement was missing from the ministry when he took over nearly two months ago.

Speaking in parliament Thursday, Yanis Varoufakis said he felt "almost infinite anger" when told that a copy of the agreement was not available, adding that one was located three and a half days after he made the request.

He blamed a tradition in Greece of ministers taking key documents with them when they leave office, and promised to change the rules to stop the practice.

Varoufakis spoke before the Greek prime minister was to hold emergency talks in Brussels with lead lenders over the country's troubled bailout negotiations.