Conservative leader David Cameron says he is not surprised that a police chiefs' report has concluded that immigration has not led to a surge in crime.

Mr Cameron hit the local election campaign trail in Kent on Wednesday with a visit to Maidstone, where the party has high hopes of taking control in May.

Asked about the findings of the report by police chiefs, he said: "I wasn't surprised by that. Immigration puts pressure on public services, in terms of housing, education and health care; it puts pressure on the police but I do not believe immigration necessarily leads to a higher crime rate."

He added: "Many people who come to Kent come to work very hard in some of the agricultural businesses.

"I wasn't at all surprised but the reason for wanting to control immigration overall is actually just the pressure on a range of public services and to make sure we can have the benefits of immigration. Labour's policy of having no limits has just not worked."

Kent police chief Mike Fuller said in response to the report by the Association of Chief Police Officers (Acpo): "There is no doubt in Kent that migration has increased the demands on police.

"It is not necessarily in terms of crime - migrants can be victims as well as potential perpetrators - but it has increased our workload, as it has to other public services such as education and health."

~ Kent's police chief responds to immigration report >>>

Mr Cameron said he did not want people to turn the forthcoming local elections into a referendum on Gordon Brown but admitted there was a "national backdrop" to all polls, especially with the state of the economy "uppermost on people's minds".

"Local elections are about local issues. I always encourage people to vote on local issues and for local candidates. But there is a national background to the local elections and there is no doubt about that," he said.

The environment was at the heart of the party's local election manifesto, along with a pledge to keep council tax down.

"There is a connection between local environment and crime. If you clean the streets, you make them safer streets; if you pick up the litter, clean up the graffiti and stop the fly-tipping you make people feel safer and improve the quality of life. That is why the vote blue, go green and the green message of modern Conservatism is not some airy-fairy idea."

Earlier Mr Cameron praised Kent for the warm welcome it gave troops returning from Afghanistan.

Speaking outside the Kent Messenger's offices in the High Street he commended the 4,000 people who attended the parade held in honour of the 36 Engineer Regiment last month and he said he hoped to go to the war zone again soon to visit the troops.

Mr Cameron met Tory election candidates during his visit, ahead of the Maidstone council poll on May 1. He also had a tour of the town centre and met Age Concern carers, clients and staff.

See this week's Kent Messenger for more.