Washington  - Long-time US Senator Ted Kennedy, who has been battling brain cancer since May, collapsed Tuesday in the middle of US President Barack Obama's inaugural lunch with members of Congress.

Obama said his prayers were with Kennedy - the brother of former president John F Kennedy - and his family.

"I would be lying to you if I did not say that right now a part of me is with him," Obama said.

Kennedy, 76, suffered a seizure towards the end of the lunch, which occurred just after Obama was sworn in as president, US media reported citing sources inside the Capitol.

Kennedy was transported by ambulance to a local hospital. (dpa)