Ash from a volcano that erupted in Iceland halted flights across nearly all of Norway and northern Sweden on Thursday.

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Flights in Northern Sweden, as well as all British Airways domestic flights, were cancelled because of the risks posed by volcanic ash, which can also damage aircraft engines.

"The cloud of ash is blowing in from Norway and affecting the western parts of Swedish air space," said Susanne Rundström at Swedavia, the firm which operates 14 publicly-owned airports in Sweden, told the TT newswire.

All air traffic at Oslo airport, Norway's biggest, was suspended at 10:00 am (0800 GMT) Thursday due to clouds of ash from a volcano eruption in Iceland, its operators said in a statement.

"All air traffic to and from Oslo Airport is cancelled ... This is due to the closure of (Norwegian) airspace due to ash from the Iceland volcano eruption," the airport said in a statement.

"All passengers should contact their airline for more information."

All air traffic in Norway was thus grounded after Norway's airport network operator earlier closed airspace in the rest of the country due to the risk that volcanic ash could cloud visibility.

Iceland's second volcano eruption in less than a month began under the Eyjafjallajokull glacier in the south of the country at around 1:00 am (GMT) Wednesday.

Between 700 and 800 people were evacuated from their homes in the remote, lightly populated area 125 kilometres (75 miles) east of Reykjavik, as melted glacier water caused massive flooding.

Last month, the first volcano eruption at the Eyjafjallajokull glacier since 1823 -- and Iceland's first since 2004 -- briefly forced 600 people from their homes in the same area.

Also more than 250 flights to and from London's Heathrow and Gatwick airports were grounded on Thursday by volcanic ash drifting from a volcanic eruption in Iceland, airport operators said.