Grozdeva celebrates winning gold at the 2004 Olympic Games in Athens, Greece [GALLO/GETTY]

Double Olympic shooting champion Maria Grozdeva has threatened to boycott the London Olympics if there is no change at the helm of the Bulgarian shooting federation.

Grozdeva, who won golds in the women's 25m pistol at the Games in 2000 and 2004, reacted angrily after her shooting club Levski Sopharma were expelled from the federation for not participating in domestic competitions.

The 39-year-old Bulgarian, who also won Olympic bronze medals in the 10m air pistol in 1992, 1996 and 2004, said she did not take part in the national tournaments because she was competing abroad at the same time.

"It's ridiculous," Grozdeva, preparing for her sixth Olympics, told bTV on Tuesday.

"He (federation chief Kamen Shishmanov) should resign or I'll not compete at the Olympics.

"Yes, it's an ultimatum," said Grozdeva, who was named Bulgaria's athlete of the year in 2004.

"Let's see who is more important."

Shishmanov said the federation had complied with the rules as all clubs needed to take part in at least one of the two
national championships during the year, something that Levski Sopharma had not done.

Bulgarian shooters have won four gold medals, six silver and six bronze at the Olympics since 1960.

Spain's Gemma Mengual is expected to announce an early retirement before the Games [GALLO/GETTY]

One of Spain's most successful athletes, synchronised swimmer Gemma Mengual, might also miss out on the London Games as she is expected to announce her retirement at a news conference on Wednesday.
 
The 34-year-old's agent on Tuesday would only confirm the details of the event, 1130 GMT in Barcelona, saying everything would be explained then.

Local media said "federation sources" had told the news agency EFE Mengual was going to bring forward her retirement to before this summer's Games.

Mengual won almost 40 medals in European, world and Olympic competitions, taking two silver medals at the 2008 Beijing Olympics in the duet and team events.

She helped Spain win gold in the free combination event at the 2009 world championships after which she took time out to have a baby son, called Nil.

Mengual, who is know as "la sirena" or the "the mermaid", returned to training last September when she said she was
determined to compete at her fourth Olympic Games in London.