ATHENS—Elena Panaritis, an aide to Greek Finance Minister Yanis Varoufakis, will be the country's new representative to the International Monetary Fund, the Finance Ministry said.

Ms. Panaritis is expected to succeed Thanos Catsambas, who stepped down in April, when his resignation takes effect on June 1.

The new representative is proposed by the Greek finance minister, but technically has to be officially approved by IMF Executive Director Carlo Cottarelli.

Mr. Catsambas, a former IMF official, was appointed Greece's representative to the IMF in 2012 during the tenure of technocrat Prime Minister Lucas Papademos.

Ms. Panaritis is an economist who has worked at the World Bank and was a member of the Greek Parliament from 2009 to 2012. Until now she has been serving as an adviser to Mr. Varoufakis and has been involved in the country's negotiations with its international creditors.

But her role in the negotiations was curbed after Greek Prime Minister Alexis Tsipras shook up the negotiating team late April, to reduce the influence of the country's high-profile finance minister, as well as his team's.

Mr. Varoufakis remained finance minister and continues to represent Greece in meetings of European finance chiefs. But the team of negotiators around him, responsible for much of the policy detail, has since then been led by Greek officials who are seen in some European capitals as more promising interlocutors. Some of Mr. Varoufakis's confidantes, including Ms. Panaritis, who were instead seen as obstructing progress in the talks have been sidelined.

According to a Greek official, Mr. Catsambas handed in his resignation after Mr. Varoufakis decided Greece's former representative to the IMF Panayiotis Roumeliotis would accompany him during his first meeting with IMF chief Christine Lagarde in April, and not Mr. Catsambas.

Ms. Panaritis is expected to be named alternate executive director to the IMF. The role is largely ambassadorial, but it has become important for Greece

The country is locked in negotiations with the institutions overseeing its bailout and has been struggling to meet payments to its international creditors, including the IMF.

Earlier this month, in an unusual move that bought the country more time, the government drew on its holdings of an IMF reserve currency to make a loan repayment of around €750 million, or about $820 million, to the IMF. Greece's departing IMF representative Mr. Catsambas was involved in arranging the maneuver, officials familiar with the matter said.

Write to Nektaria Stamouli at nektaria.stamouli@wsj.com

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