Illinois Governor, George Ryan, said he came to build bridges and exchange ideas.

Correspondent Tom Gibb: "Lobbying power having an effect in Washington"

Governor Ryan, leading a 45-member delegation, is expected to meet President Castro and other government officials.

He also plans to donate $1m dollars in humanitarian aid.

The official Cuban newspaper Granma welcomed the visit as a sign of eroding support for the US economic embargo on the island, introduced in 1962.

On his arrival Mr Ryan quoted Abraham Lincoln: "The probability that we may fail in the struggle should not deter us from support of a cause that we believe to be just."

Sanctions issue

Mr Ryan and a growing band of US politicians are championing the easing of the US embargo against Cuba, at least sufficiently to allow US farmers and pharmaceutical companies to sell their products to the island.

The delegation includes representatives of two of the biggest US agricultural companies, as well as an Illinois-based pharmaceutical company.

George Ryan, the first US governor to visit Cuba in 40 years

Mr Ryan says on his website: "It is my belief - and the belief of many people in Illinois - that isolating the Cuban people is a policy that is not in the best interests of Cuba, of Illinois, or of the United States.

"I don't think we should use the staples of life as a political weapon."

Cuba's Foreign Ministry has welcomed the visit as "a reflection of the growing rejection by different sectors of US society towards the current hostile policy and embargo against Cuba."

Anti-Castro groups in the US said he was lending credibility to Castro and a government responsible for rights abuses.