There's no difference in the word itself between American and British English. However, there are some subtle differences in how the word is used in certain contexts.
For example:
* Queue: In British English, "queue" is often used to refer to a line of people waiting for something, whereas "line" is more common in American English.
* Telephone line: Both British and American English use "telephone line", but in British English, "phone line" is more common.
Overall, though, "line" is the standard word for the concept in both varieties of English.