Gul underwent an operation last year in Melbourne after suffering a recurrence of knee injury.
"The reports about Gul are not very encouraging and there are very slim chances that he will be considered for the final World Cup squad," Khan told PTI.
Gul has struggled to touch top fitness and bowling form since completing the rehabilitation period after the knee surgery last year in May.
Last month again he had to return home from the UAE after his knee problem relapsed during the one-day series against New Zealand.
Khan said, "Gul had also been playing in domestic cricket this season and had bowled number of overs but for some reason as soon as he was inducted for international cricket he faced fitness problems".
Gul, who has appeared in 47 Tests and 125 ODIs for Pakistan, has been the national team's most potent pacer in recent years before he suffered the knee injury.
Junaid has also been named to lead the Khyber Pakhtunkhawa team in the Pentanglar one-day cup, which begins from December 31.
Khan said that the selection of suspended off-spinner, Saeed Ajmal and Muhammad Hafeez in the final World Cup squad would depend on clearing the informal tests at the bowling centre in Chennai this week.
"If they clear the informal tests, they will be sent immediately for the ICC official tests to get their bowling actions cleared," he said.
"No gamble will be taken with any player who does not attain peak fitness," he said.
