Alleging that China is "not allowing" entry of ships with Indian crew onboard, All India Seafarer & General Workers Union has sought the central government's help in saving the jobs of thousands of Indian seamen, as companies are not recruiting them for the China-bound ships.In a letter to Union Minister for Ports, Shipping and Waterways Sarbananda Sonowal, the seafarers' body has said that as many as 20,000 seafarers are "home" because of this reason."From March 2021, any ship reaching China Port and having Indian seafarers as a crew on it, China government is not allowing all those ships to enter into the port," it said in the letter posted on its Twitter handle.The copies of the letter have also been marked to the Ministry of External Affairs and sector regulator, Directorate General of Shipping."Because of this reason, the companies have stopped recruiting seafarers from India to join the vessel. Approximately, 20,000 seafarers are home because of this reason," it stated."The union (is) requesting you ... all the higher authorities (to) look into this serious issue and help us to save the job of our seafarer brothers," the seafarers' body said in the letter.According to it, around 80 per cent of seafarers on various ships come from India and "without them, the shipping industry will collapse and will be in big disaster".