LONDON - Growing concern over the state of Britain's ailing public health and transport systems has tarnished public support for Prime Minister Tony Blair and his Labour government, a poll published on Thursday showed.

The MORI poll for the Times newspaper said that the National Health Service (NHS), at the centre of a bitter political row over patient care and standards, has become a top priority for the public amid easing fears over the risk of terror attacks post-September 11.

At the same time, support for Blair and his government has dropped five points to 51 percent since a similar poll in November.

Two thirds of the public now regard the NHS as among the most important issues facing Britain -- a 17 point jump over the past two months, the survey said.

Health has become a major political issue in Britain following a series of scandals and crises which have forced Blair to pledge more public money for the overcrowded state-run health system.

Transport, which like health has hit headlines in recent weeks, has also shot up the public agenda due to a series of crippling rail strikes. Concern has more than doubled in the last two months with 22 percent of people naming it as a top priority without being prompted, compared with 10 percent in November.

By contrast, the number of people naming defence, terrorism and foreign affairs as top priorities for Britain slid to 13 percent, down from 40 percent in November and 60 percent in late September.

Concern over the state of the NHS is now at the highest level since a serious influenza outbreak in January 2000, which was in turn the highest level recorded, the Times said.

The public has also become less pessimistic about the economy. The MORI economic optimism index, which measures the proportion of people who think general economic conditions will get better rather than worse over the next year, stands at minus 20. This compares to minus 29 in November and minus 56 in late September.

The MORI poll interviewed 1,955 adults across Britain.