LONDON (REUTERS) - A Sudanese migrant walked the 50km Channel Tunnel from France, dodging high-speed trains and evading security guards before he was stopped just short of the British entrance and arrested.

Thousands of migrants from Africa and the Middle East have been trying to flee makeshift camps in the French port of Calais and enter Britain illegally by jumping onto lorries and hiding on trains, disrupting cross-Channel freight and passenger traffic.

British police said Abdul Rahman Haroun, 40, was found close to the British entrance to the tunnel near Folkestone in south-east England on Tuesday evening.

Police said he had been charged with "causing an obstruction to an engine or carriageway using the railway", and would appear in court.

British Prime Minister David Cameron said last month that he was going to take action to resolve the crisis, including beefing up security at the terminal in Calais, but he warned there was no quick fix.

The government said on Friday it was working with the French government and operator Eurotunnel to resolve the crisis. Eurotunnel did not immediately respond to requests for comment on the arrest.

The government said more than 39,000 attempts to cross the Channel illegally were prevented in 2014 to 2015, more than double the previous year.