ATHENS (Reuters) - Greece needs to move swiftly to secure a positive review of its economic reforms by lenders in coming weeks and start discussions on debt relief, Prime Minister Alexis Tsipras said on Friday.

The firebrand leftist cemented his position as Greece's dominant political figure in national elections on Sunday in which his Syriza party won 145 of 300 parliamentary seats.

But he faces a dauntingly long "to do" list that includes implementing the austerity mandated by Greece's international creditors, negotiating debt relief and dealing with waves of migrants landing on Greek shores.

"Debt restructuring will reduce investment risks and make our economy once again attractive to investors," Tsipras told ministers in the first meeting of his cabinet.

Other priorities, he said, included a recapitalization of Greece's banks, which, "if done correctly, can give our economy badly needed liquidity."

Greece's 86 billion euro ($96 billion) bailout package, its third since 2010, is contingent on pension reform, ending tax breaks, labor reforms, and privatizations.

Of that amount, up to 25 billion euros has been set aside for shoring up the capital of banks, hobbled by deposit flight earlier this year and a mountain of non-performing loans, a consequence of a crippling six-year economic recession

Greece has also become the main point of entry into Europe for migrants fleeing war and poverty in theMiddle East.

Hundreds are reaching its shores every day, most of whom then head by land across the Balkan peninsula to richer EU countries further north.

Generally sympathetic to the plight of migrants, Greece has highlighted discord among its EU partners on how best to deal with Europe's worst humanitarian crises in decades.

"We have to decide what Europe we want," Tsipras said. "Do we want a Europe of solidarity or one which throws teargas, showing these people its harsh side?"