Greece increased the pressure on its creditors late on Tuesday, as it looks to secure a bond swap deal that will help write off an estimated 53.5 percent of the country's privately held debt.

Athens informed creditors that it is reassessing its options concerning non-payment, saying it will default on any bondholders unwilling to participate in the €206bn debt restructuring.

Private creditors in Greece now have until Thursday to decide. New legislation has already been passed to force bondholders to participate.

Greek banks, which hold up to €45bn of the sovereign bonds already agreed to take part in the debt swap deal, Greece's finance minister Evangelos Venizelos said.

France's Societe Generale and Italy's UniCredit also joined the participating Greek banks on Tuesday.