A Guardian newspaper survey carried out last weekend showed 57% of those asked said Nato strikes should continue.

This is almost the same figure as the 56% of those in favour of the action just after the bombing started at the end of March, although it is down from a peak of 65% in favour three weeks ago.

Rise in number of undecided

But the refugee convoy attack may have been behind a surge in the "don't knows", which leapt from 11% to 22% of those questioned.

An NOP poll for GMTV also found majority support for the air strikes.

About 55% of those questioned said the bombing should continue, with 34% opposed. Only 11% said they did not know.

Hostility to the air war has fallen from 24% to 21% in the past three weeks, according to the ICM poll.

Split over ground troops

The two polls showed opinion was divided on the issue of whether or not to send in ground troops. The Guardian poll found 50% of those asked were in favour, compared with 48% of those questioned by GMTV.

The UK Government remains steadfast in its resolve to continue air strikes until Serbia's President Slobodan Milosevic backs down.