An Italian member of the creditor mission auditing Greek reforms was hospitalised in Athens last week after suffering a stroke, a Greek weekly said Sunday.
To Vima weekly said Giovanni Callegari, a 38-year-old economist at the European Central Bank, collapsed Thursday in the finance ministry where the talks are mainly held.
He remains in intensive care but is believed to have escaped danger, the newspaper said.
Talks over Greece's recovery programme, which have continued since the start of the country's multi-billion bailout in 2010, have been long and often tense.
The discussions had been suspended last month, and when they resumed last week, Finance Minister Yannis Stournaras told the creditors that the government could fall if more austerity measures were imposed on the recession-weary nation, To Vima said.
The heads of the tripartite EU-IMF-ECB mission known as the troika were meeting with Prime Minister Antonis Samaras on Sunday to try to unblock a number of stalled issues.
These include civil service job cuts, a revised property tax and an ongoing merger between Greece's top and third-ranked lenders, National Bank and Eurobank.