The Treasury said Tuesday that Lew will meet with European Central Bank President Mario Draghi in Frankfurt on Wednesday.
The following day Lew will have talks in Berlin with German Finance Minister Wolfgang Schäuble, and then in Paris with French Finance Minister Michel Sapin.
The Treasury said the aim of the talks was "to continue engagement with European counterparts on the ongoing situation in Greece," which still needs to pass certain basic reforms to proceed on finalizing the bailout.
On Monday Lew hailed the agreement between Greece and European Union official creditors as a crucial step toward rebuilding trust and reviving the Greek economy.
He added that Greece's reform pledges "will require difficult steps by all of the parties and substantial work remains to be done."
Tsipras on the hook
Lew arrives at a critical point, as Prime Minister Alexis Tsipras seeks to push legislation through the Greek parliament that will allow him to begin negotiations with the country's creditors for a third financial aid programme.
In a Greek TV interview on Tuesday night, Tsipras said that he wouldn't rule out stepping down and calling fresh elections once the vote was over.
But he continued to reserve special criticism for Germany, warning that "Europe doesn't belong to Herr Schäuble“ and that the deal reached on Monday for a possible new bailout programme "doesn't honour the tradition of Europe."
Germany's opposition Green party tends to agree with Tsipras.
"That a German government should publicly push for a step backwards in European integration is a 180-degree turn in German Europe policy since [the founding of the Federal Republic in] 1949," financial policy spokesman Gerhard Schick told the Südwest Presse on Wednesday.