Hundreds of protesters have crowded into the Alabama Statehouse courtyard to demonstrate against the state's immigration law that is among the toughest in the United States.

Protesters chanted in English and Spanish before moving into the building to deliver heart-shaped lollipops and Valentine's cards calling for the law's repeal.

Alabama legislators declare they will introduced a bill in the coming weeks to make subtle changes to the law but insist that it will not be overhauled.

Zayne Smith, co-ordinator of the Alabama Coalition for Immigrant Justice, said the rally was intended to send a message of love and respect for immigrants.

She said proposed amendments to the law will not go far enough and a full repeal is needed.

Elois Zeanah, president of the Alabama Federation of Republican Women, said in a statement that the law was working to lower unemployment.