Romina Sala travelled to the UK on Thursday to meet with Cardiff City officials as efforts continued to find the Argentine and 60-year-old pilot David Ibbotson, only for the search to be ended at 3:15pm. Investigators now say they will examine whether the pilot had the correct licence.

Following almost four days of searches, which have failed to locate any trace of the missing aircraft, Guernsey harbour master Captain David Barker said “the chances of survival at this stage are extremely remote”.

But immediately after the search was called off, Romina issued a heartfelt plea to continue efforts to locate her brother, and said that to the family he remains alive until proven otherwise.

“We understand the facts and we really appreciate the efforts,” she said to media outside the St David’s Hotel in Cardiff. “We want to say thanks to the two clubs [Cardiff City and Nantes FC] and everyone who is looking for Emiliano, but my message is please, please, please don’t stop with the search. For me, they are still alive.

Emiliano Sala: Career in pictures Show all 12 1 /12 Emiliano Sala: Career in pictures Emiliano Sala: Career in pictures Emiliano Sala Cardiff City striker Emiliano Sala is missing and feared dead after an aeroplane carrying him and one other person went missing over the English Channel AFP/Getty Emiliano Sala: Career in pictures Emiliano Sala He first moved to France in 2011 before joining Bordeaux and making his debut in 2012 Getty Emiliano Sala: Career in pictures Emiliano Sala Sala arrived at Bordeaux after playing for Club Proyecto Crecer in Argentina Getty Emiliano Sala: Career in pictures Emiliano Sala In Ligue 1, Sala found himself going up against some of the best-known defenders such as PSG’s David Luiz Getty Emiliano Sala: Career in pictures Emiliano Sala He would join Caen on loan in 2015 Getty Emiliano Sala: Career in pictures Emiliano Sala While with Bordeaux, Sala also spent time on loan with US Orleans and Chamois Niort Getty Emiliano Sala: Career in pictures Emiliano Sala In 2015, Sala secured a move to Ligue 1 side Nantes EPA Emiliano Sala: Career in pictures Emiliano Sala Sala played 130 times for Nantes, scoring 48 goals in all competitions AFP/Getty Emiliano Sala: Career in pictures Emiliano Sala His form in France saw him catch the eye of a number of clubs around Europe AFP Emiliano Sala: Career in pictures Emiliano Sala Sala was the fifth-highest goalscorer in Ligue 1 this season with 12 goals in 19 games Getty Emiliano Sala: Career in pictures Emiliano Sala Sala agreed to join Cardiff in a club-record £15m deal on Saturday 19 January Cardiff City Emiliano Sala: Career in pictures Emiliano Sala Sala’s flight to Cardiff went missing on Monday 21 January and is believed to have crashed into the English Channel Getty

“It is very difficult to express my feelings at the moment because it is really hard.

“We have had a lot of support from the two clubs and I thank all the fans for their efforts, but deep down in the bottom of my heart I know that Emiliano – who is a fighter – is still alive. I know Emiliano and the pilot are somewhere in the middle of the Channel.

“We are not going to give up.”

Investigators will inspect whether Mr Ibbotson had the correct licence, it has since emerged.

The Air Accident Investigation Branch has opened a probe since the light aircraft disappeared from radar on Monday night. ”We are looking at all operational aspects of the flight including licensing,” a spokesman said.

Mr Ibbotson, 59, of Crowle, Lincolnshire, held a private pilot’s licence and passed a medical exam as recently as November, according to Federal Aviation Administration records in the US, where the plane was registered.

A widespread search of the Channel Islands and the surrounding areas saw three planes, five helicopters and two lifeboats search more than 1,700sq miles of water after the aircraft disappeared off radars on Monday night, but efforts were brought to a halt when officials felt that all options had been exhausted.

A number of passing vessels and aircraft had also offered their help with the search, but no trace of the missing plane had been found. The fact that the initial search efforts on Monday night had to be abandoned after 2am due to worsening weather conditions may have proved a significant setback to establishing where the plane disappeared.

The incident will remain open and all boats and aircraft in the area will be contacted to remain alert for any objects or signs in the water of a potential wreck, but the coastguard will no longer actively search for the two men and plane unless there are any major developments.

Sala went missing on Monday after his flight disappeared (AFP/Getty)

“My team have just met to review the search and rescue operation which has been underway since the plane disappeared on Monday night,” Captain Barker said. “Despite the best efforts of air and search assets from the Channel Islands, UK and France, which has covered an area of approximately 1,700sq miles – with a significant amount of this searched more than once – and having examined mobile phone data and satellite imagery, we have been unable to find any trace of the aircraft, the pilot or the passenger.

“There has been over 24 hours of continuous searching, with 80 hours combined flying time across three planes and five helicopters. Two lifeboats have also been involved, as well as assistance from various passing ships and fishing boats.

“We reviewed all the information available to us, as well as knowing what emergency equipment was on board, and have taken the difficult decision to end the search.

“The chances of survival at this stage are extremely remote.

The Piper Malibu light aircraft was travelling from Nantes in western France to Cardiff (Getty)

“[Sala’s and Mr Ibbotson’s] next of kin have been informed of this development, and my thoughts go out to the family of the pilot and passenger at this most difficult of times.