Spanish Royals Host A Dinner Gala For President Of Portugal Marcelo Rebelo De Sousa at the Royal Palace on April 16, 2018 in Madrid, Spain.

(L) Queen Letizia of Spain wore a floor-sweeping blue gown with cut out detailing under the arms and at the back, as she meets Spanish tennis player Garbine Muguruza, alongside with Portuguese President Marcelo Rebelo (C) and her husband King Felipe VI of Spain (R) as they attended a state dinner 2018 at the royal palace in Madrid

King Felipe VI of Spain (R) and Queen Letizia of Spain, who wore a show-stopping pearl tiara first owned by Queen Victoria Eugenia in 1906, host a dinner gala for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace on April 16, 2018, in Madrid, Spain.

(L-R) Queen Letizia of Spain's striking blue gown was a far cry from the more demure clothes she is known for, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain greet guests during a dinner gala 2018 for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace in Madrid, Spain.

(L-R) Queen Letizia of Spain, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain attend a dinner gala for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace on April 16, 2018, in Madrid, Spain.

(L-R) Queen Letizia of Spain, President of Portugal Marcelo Rebelo de Sousa, who greet Spanish Prime Minister Mariano Rajoy and King Felipe VI of Spain greet guests during a dinner gala 2018 for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace in Madrid, Spain.

(L-R) Queen Letizia of Spain, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain attend a dinner gala for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace on April 16, 2018, in Madrid, Spain

(L-R) Queen Letizia of Spain, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain attend a dinner gala for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace on April 16, 2018, in Madrid, Spain

(L-R) Queen Letizia of Spain, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain, mingled with Spanish Prime Minister Mariano Rajoy as they greet guests in a dinner gala 2018 for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace in Madrid, Spain.

(L-R) Queen Letizia of Spain, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain attend a dinner gala 2018 for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace in Madrid, Spain.

(L-R) Queen Letizia of Spain, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain attend a dinner gala 2018 at the Royal Palace in Madrid, Spain. During the evening, King Felipe spoke of the unity between Spain and Portugal and their shared values.

King Felipe VI of Spain (R) and Queen Letizia of Spain's modern-dress had a pearl detail from top to bottom, and she accessorized with a regal red sash as they host a dinner gala 2018 for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace in Madrid, Spain.

(L-R) Queen Letizia of Spain's racy gown had a slash on the side and flashed a peak of The Queen's thigh as she walked, President of Portugal Marcelo Rebelo de Sousa and King Felipe VI of Spain attend a dinner gala 2018 at the Royal Palace in Madrid, Spain.

Queen Letizia of Spain's Cartier Diamond and Pearl Tiara was given to Queen Victoria Eugenia, known as Queen Ena, as a wedding present from her own mother-in-law Queen Maria Cristina of Spain

Queen Letizia of Spain wore a Cartier Diamond and Pearl Tiara that once belonged to the former Queen Sofía as she joined her husband for an opulent state banquet 2018 in Madrid.

Queen Letizia of Spain looked resplendent in a Madrid-based designed gown by Ana Locking along with Nina Ricci heels and a stunning Cartier tiara. The blue gown certainly made Queen Letizia stand out from the crowds as she joined her husband at the evening event at the Royal Palace in Madrid.

Queen Letizia of Spain's striking pearl embellished dress featured cut-out detailing around her underarm and back, flashing just a hint of her skin and she accessorized with a regal red sash, during a state dinner at the Royal Palace in Madrid

Queen Letizia of Spain attended the event at the Royal Palace in the Spanish city in a floor-sweeping blue gown with pearl embellished, cut out detailing under the arms and at the back by Ana Locking and the striking headwear.

Queen Letizia of Spain wore dark eye makeup and a dash of mauve lipgloss and stuns in Cartier Diamond and Pearl Tiara as she attended the swanky event at the Royal Palace in Madrid

Queen Letizia of Spain looked regal as she offered President Rebelo de Sousa of Portugal a cheek to kiss before the start of the glamorous dinner as she joined her husband King Felipa VI of Spain at the evening event

(L-R) Queen Letizia of Spain's blue dress flaunted her slim figure as they greeted guests with President of Portugal Marcelo Rebelo de Sousa and husband King Felipe VI of Spain during a dinner gala 2018 at the Royal Palace in Madrid, Spain.

The Cartier Diamond and Pearl Tiara have been worn by Queen Letizia's mother-in-law Queen Sofia of Spain during several state events pictured during the wedding of Crown Prince Frederik and Mary Donaldson in Copenhagen on May 14, 2004.

Queen Letizia of Spain dazzled in Ana Locking spring 2017 pearl embellished blue gown along with Nina Ricci heels and a stunning Cartier tiara and Pearl Tiara, as she attends a state dinner 2018 at the Toyal Palace in Madrid

Queen Letizia of Spain in a floor-sweeping blue gown with pearl detailing by Ana Locking and the striking Cartier Diamond and Pearl Tiara, attended a state dinner with her dapper husband King Felipe VI of Spain at the Royal Palace in Madrid

Queen Letizia of Spain's striking pearl embellished dress featured cut-out detailing around her underarm and back, flashing just a hint of her skin and she accessorized with a regal red sash and a stunning Cartier tiara, during a state dinner 2018 at the Royal Palace in Madrid

(L-R) Queen Letizia of Spain and President of Portugal Marcelo Rebelo de Sousa greet guests during a dinner gala 2018 at the Royal Palace in Madrid, Spain.

Queen Letizia looked resplendent in an Ana Locking spring 2017 pearl embellished gown along with Nina Ricci heels and a stunning Cartier tiara, attended the event at the Royal Palace in Madrid

Queen Letizia of Spain dazzle in a pearl embellished blue gown attended a state dinner with her husband King Felipe VI of Spain, who looks dapper in black tux in Madrid.

Queen Letizia of Spain wore a floor-sweeping pearl embellished blue gown with cut out detailing under the arms and at the back by Ana Locking and a stunning Cartier Diamond and Pearl Tiara, attended the event at the Royal Palace in the Spanish city of Madrid.

Queen Letizia of Spain in a floor-sweeping Ana Locking blue gown with pearl detailing from top to bottom, and she accessorized with a regal red sash and striking Cartier Diamond and Pearl Tiara, during a state dinner 2018 at the Royal Palace in Madrid

The Ana Locking blue gown certainly made Queen Letizia of Spain stand out from the crowds as she joined her husband Kig Felipe VI of Spain at the evening event at the Royal Palace in Madrid.

Queen Letizia of Spain wore a striking blue gown by Ana Locking and a stunning Cartier tiara, hosts a dinner gala 2018 for the President of Portugal Marcelo Rebelo de Sousa at the Royal Palace in Madrid, Spain.

Queen Letizia of Spain wore a floor-sweeping pearl embellished blue gown with cut out detailing under the arms and at the back by Ana Locking and a stunning Cartier Diamond and Pearl Tiara, attended the event at the Royal Palace in the Spanish city of Madrid.