After nearly 20 years together, Penny Wong and Sophie Allouache tie the knot

The couple's nuptials were held in Adelaide, with a guest list that included Prime Minister Anthony Albanese and other senior ministers.

Foreign Minister Penny Wong (right) and Sophie Allouache have married after nearly two decades together. Source: Instagram / @senatorpennywong

Foreign Minister Penny Wong and Sophie Allouache have tied the knot after nearly two decades together.

The couple were married in Adelaide on Saturday in a ceremony attended by Prime Minister Anthony Albanese and senior ministers.

The couple's two daughters - Alexandra, 11, and Hannah, 8 - were reportedly flower girls at the wedding.

"We are delighted that so many of our family and friends could share this special day with us," the Labor senator posted to Instagram on Sunday.

Parliamentary colleague Michelle Rowland was among those to congratulate the couple.

"You both look absolutely gorgeous," she said.

Entering federal parliament in 2002, Wong recently made history as Australia's longest-serving female cabinet minister.

Penny Wong (right) with partner Sophie Allouache and their daughter Alexandra in Adelaide, 2011. Source: AAP, Supplied / Penny Wong

She initially toed the Labor line by publicly opposing same-sex marriage before becoming one of its loudest and most ardent advocates.

During the parliamentary debate in 2017 to expand marriage to same-sex couples like hers, the senator paid tribute to her partner Sophie and their daughters.

"This is the most personal of debates because it is about the people who matter most to us," she said.