More than 6,250 people have died in the swine flu pandemic, World Health Organisation data has showed, as the global death rate appeared to slow.

The number of deaths from the A(H1N1) pandemic in the week to November 8 grew by about 179, against 224 a week earlier and a leap of about 700 in the last week of October.

The pandemic now stretches across 206 countries or territories worldwide, the WHO added in a statement.

The UN health agency said the influenza season showed signs of peaking in North America, but was intensifying across much of Europe and Central and Eastern Asia.

"Very intense and increasing influenza activity continues to be reported in Mongolia with a severe impact on the health care system," it added.

But the WHO found after investigating the sudden reported surge in flu cases in Ukraine in recent weeks that the swine flu virus had shown no signs of becoming stronger.

"The initial analysis of information indicates that the numbers of severe cases do not appear to be excessive when compared to the experience of other countries and do not represent any change in the transmission or virulence of the virus," the statement said.

More than 1.3 million Ukrainians have been taken ill with swine flu and 265 people have lost their lives to the virus since the end of October, the country's health ministry said on Friday.