ATHENS (Reuters) - Greek Finance Minister Yanis Varoufakis said Athens must reach a reforms deal with its European Union and International Monetary Fund lenders to unlock aid by early June. "This deal must be concluded by the first week of June," Varoufakis said at an Athens business event. Athens is running out of cash but a deal for aid has been held over disagreement on pension, labor reform and fiscal targets. Varoufakis also added that a bank transaction levy was "on the negotiating table" with EU/IMF lenders and said Athens had alternative proposals to a value-added tax hike the country had been preparing. "We are flexible in the negotiations with the lenders in Brussels and we have a plan B and C on VAT," he said. He also said he personally believed that the IMF did not want to participate in any deal involving Greece after June, when the current bailout expires. (Reporting by Lefteris Papadimas; Writing by Renee Maltezou, editing by Deepa Babington)