Dame Thea Muldoon has died.

The wife of former Prime Minster Sir Robert was 87.

The couple married in 1951 after meeting through the Junior Nationals.

They had three children. Lady Muldoon was appointed a Dame Commander in the 1993 New Year Honours.

Prime Minister John Key has expressed his sadness at her passing.

Key says Dame Thea made a significant contribution to her community and the country.