"I would like Greece to remain in the eurozone," Merkel said, according to excerpts of an interview released ahead of publication in Friday's edition of the Frankfurter Allgemeine Zeitung daily.
"All my work in connection with the eurozone crisis was aimed and is aimed at strengthening the eurozone as a whole, with all its members, including Greece."
Much had been achieved towards this goal, she said, adding that the basis for all European efforts was always the principle of solidarity in return for individual efforts and responsibility.
"This principle continues to apply for us in the cooperation with every Greek government," Merkel said.
The radical left-wing Syriza party is expected by many observers to win the early elections on January 25.
Syriza wants to abandon the austerity policy imposed by the European Union and the International Monetary Fund as part of the country's €240 billion bailout.
Germany, as the paymaster for eurozone bailouts, spearheaded a drive to demand major spending cuts in exchange for any aid, insisting that budgetary discipline offered the only long-term solution to the debt crisis.
Earlier this month, Der Spiegel news weekly cited sources close to the German government as saying Merkel was prepared to let Greece leave the eurozone if Greeks elect a government that jettisons the country's current austerity course.
Berlin did not deny the report but stressed that the government wanted Greece to stay in the eurozone and that it had not changed its position.