Foreign leaders are canceling their flights to Poland on Sunday to attend the funeral of Polish leader Lech Kaczynski and his wife over the spread of a volcanic ash cloud from Iceland.

Kaczynski and his wife Maria, who along with a delegation of senior officials died in a plane crash near the western Russian city of Smolensk on April 10, will be buried in Krakow on Sunday.

The Polish Foreign Ministry has told RIA Novosti that U.S. President Barack Obama, German Chancellor Angela Merkel, French President Nicolas Sarkozi, Italian Prime Minster Silvio Berlusconi and some other foreign leaders would be unable to attend the funeral in Krakow.

The eruption on the Eyjafjallajokull Glacier in Iceland, which began on Wednesday, has disabled air traffic throughout central and northern Europe, leaving thousands of travelers stranded. The cloud is expected to remain there for four to five days.

Meanwhile, Russian President Dmitry Medvedev flew to Poland on Sunday to attend the funeral of Polish leader Lech Kaczynski and his wife, the Kremlin press office said.

KRAKOW (Poland), April 18 (RIA Novosti)