John Kerry's wife in 'critical condition' in hospital

Teresa Heinz Kerry, 74, became ill during a family holiday in Nantucket, Massachusetts

The wife of US secretary of state John Kerry, is in critical but stable condition in a hospital in Massachusetts.

A family friend said Teresa Heinz Kerry, 74, was taken to hospital in Boston with an apparent seizure, arriving in a critical condition although doctors had stabilised her.

Ms Heinz Kerry is the widow of former US senator John Heinz, heir to the Heinz ketchup fortune. She married Mr Kerry in 1995. Doctors treated her for breast cancer in 2009.

Mr Kerry has been at their home since returning early from a nearly two-week round-the-world diplomatic trip to the Middle East and south-east Asia on July 3.

He originally planned to return to Washington and then co-host with treasury secretary Jack Lew high-level strategic and economic talks with senior Chinese officials.

Mr Kerry had also spoken of his desire to make his sixth trip to Israel as secretary starting at the end of the week.

State Department officials said Mr Kerry's schedule may now change depending on his wife's health.

AP