* Biden praises Scholz for Ukraine crisis response
* Biden, Scholz discuss food insecurity, China challenge
* "I haven't skied in a while", Biden says, admiring Alps (Adds White House readout)
By Andrea Shalal and Thomas Escritt
SCHLOSS ELMAU, Germany, June 26 (Reuters) - U.S. President Joe Biden thanked German Chancellor Olaf Scholz for his leadership on the Ukraine crisis when they met at a Bavarian Alpine retreat on Sunday ahead of a summit of the Group of Seven rich democracies that aims to send a message of unity.
Critics, including Kyiv and its western allies have accused Germany of dragging its feet in its support for Ukraine, a charge Scholz has denied.
Biden, fresh from mass administered to him in Schloss Elmau by a U.S. army chaplain, told Scholz that his leadership had been crucial in marshalling Europe's response to Russian President Vladimir Putin's invasion of Ukraine.
"I want to compliment you on stepping up as you did when you became Chancellor," Biden told a beaming Scholz. "Putin's been counting on it from the beginning, that somehow NATO and the G7 would splinter, but we haven't and it's not going to," he said.
Biden has publicly lauded Germany for agreeing to boost its military spending with a special 100 billion euros fund and overcoming resistance born of its troubled Nazi past to provide weapons to Ukraine.
But Scholz has been under fire at home and in eastern Europe for alleged dithering over what kind of weapons Europe's richest country should send Kyiv in its fight against Russian forces in its east. Scholz has always rejected these criticisms.
"It's a good message that we all managed to stay united, which, obviously, Putin never expected," Scholz said, before he and Biden moved to an open-air conference room where they held bilateral talks with a handful of close advisers.
The U.S. and German leaders discussed global food security in the wake of Russia's invasion of Ukraine and ways of addressing the challenge posed by China, the White House said in a statement.
Scholz has said that the summit's key aim is to send the message that Western sanctions on Russia are not to blame for spiraling food prices that are causing growing hunger in the Global South.
The short exchange between Scholz and Biden captured on camera was good humored.
"It's beautiful," Biden said, admiring the Bavarian mountains. "I used to ski too, but I haven't skied in a while." (Reporting by Andrea Shalal and Thomas Escritt; Additional reporting by Sarah Marsh; Editing by Toby Chopra and Raissa Kasolowsky)