By Renee Maltezou and Lefteris Papadimas
ATHENS (Reuters) - Greece's Socialist PASOK party could support a government led by the radical leftist Syriza party as part of a wider pro-euro alliance to steer the country out of its bailout programme, PASOK leader Evangelos Venizelos told Reuters.
Venizelos, who is deputy prime minister and foreign minister in the outgoing conservative-led two-party coalition, said PASOK wants a broader consensus after a general election on Sunday which the anti-bailout Syriza appears likely to win.
"Syriza alone, or allying only with Syriza is not enough," Venizelos, the 58-year-old veteran of Greek politics said in an interview. "We want to be a national partner, not necessarily a government partner, but if the country needs us we are willing to help."
PASOK once dominated Greek politics and won power outright in 2009, just before the country sank into a debt crisis, but voters began deserting in droves after it imposed austerity policies in exchange for bailout loans from the European Union and IMF. For the past three years it has served as a junior partner in the coalition of Prime Minister Antonis Samaras.
Opinion polls show Syriza widening its lead but failing to win outright on Sunday. During the campaign it has resisted talk of an alliance with anyone apart from the Communists, but has promised to seek a wider consensus after the election.
PASOK, alongside two other small centre-left parties, has been considered a potential ally that would exercise a moderating influence on Syriza, which has worried financial markets and fellow euro zone governments with its promise to renegotiate Greece's huge debt and abandon austerity.
Venizelos said any alliance with Syriza and other parties would depend on their committing to completing pending bailout negotiations with the EU and IMF and moving to a post-bailout programme without any risky moves.
"The conditions are that they all understand that rushed, amateur proposals are dangerous and increase the country risk," said Venizelos. He added that there was a "risk of a shock or disappointment compared with the expectations created" by Syriza's "easy promises".
PASOK, which stormed to power with 44 percent of the vote in 2009, now ranks fourth or fifth in the polls with just 3 to 5 percent of the vote. It suffered another setback when former leader and ex-prime minister George Papandreou broke away to set up a rival party three weeks ago.
Venizelos, who served as finance minister at the peak of the crisis and oversaw a debt restructuring in 2012, said it was "unlikely" Greece would leave the euro but warned the pre-election period had hurt state finances.
"No one wants it, but what's important is to avoid any accidents," he said, referring to a Greek exit from the euro zone.
Venizelos, whose political career spans more than two decades, also called on EU leaders to respect Greece's sovereignty and avoid intervening in the election campaign. He made the comment after some European policymakers publicly warned Greeks against voting anti-bailout leftists into power, saying any new government must respect commitments made so far.
"Addressing European leaders, I want to ask them to respect the dignity and sovereignty of the Greek people. Greek people must choose their future and their government," he said.
"Europe and the international system must negotiate with the legal Greek government."
(Writing by Deepa Babington; editing by David Stamp)