Hungary's prime minister, one of the strongest European critics of Chancellor Angela Merkel's approach to the migrant crisis, has made a politically charged visit to her predecessor and one-time mentor, Helmut Kohl.

Viktor Orban traveled to Kohl's home in southwestern Germany Tuesday for what Kohl's office termed a private visit between friends. Still, it has been widely interpreted in Germany as a swipe by Kohl at Merkel over her relatively liberal approach to welcoming refugees.

A joint statement by Kohl's office and the Hungarian embassy said that Europe "cannot be the new home for millions of people in need worldwide." However, it added that Kohl and Orban don't oppose Merkel's efforts to resolve the crisis.