Integrated process for the synthesis of ammonia and nitric acid, comprising a synthesis of nitric acid including the following steps: a) subjecting a stream of ammonia to oxidation, obtaining a gaseous stream containing nitrogen oxides; b) subjecting said gaseous stream to a process of absorption of nitrogen oxides, providing nitric acid and a first tail gas containing nitrogen and residual nitrogen oxides; c) subjecting at least a portion of said first tail gas to a process of removal of nitrogen oxides, providing a second tail gas containing nitrogen and having a lower content of nitrogen oxides than said first tail gas, and comprising a synthesis of ammonia by catalytic conversion of a make-up gas (126, 226) comprising hydrogen and nitrogen in an ammonia synthesis loop, wherein at least a portion (18b, 18d, 21) of said second tail gas is a nitrogen source for said make-up gas (126, 226), and wherein the first tail gas provided by said step b) is entirely or substantially entirely subjected to said NO x -removal step c) and the resulting NO x -depleted tail gas splits into two portions, a first portion being used as nitrogen source to obtain said ammonia make-up gas and a second portion being work-expanded to produce power, or wherein the first tail gas provided by said step b) splits into two portions, a first portion being subjected to said removal step c) and a second portion being subjected to a further step for removal of NO x, thus providing two streams having a lower content of nitrogen oxides than said first tail gas, a first stream being a nitrogen source for said ammonia make-up gas and a second stream being work-expanded to produce power. a) subjecting a stream of ammonia to oxidation, obtaining a gaseous stream containing nitrogen oxides; b) subjecting said gaseous stream to a process of absorption of nitrogen oxides, providing nitric acid and a first tail gas containing nitrogen and residual nitrogen oxides; c) subjecting at least a portion of said first tail gas to a process of removal of nitrogen oxides, providing a second tail gas containing nitrogen and having a lower content of nitrogen oxides than said first tail gas, and comprising a synthesis of ammonia by catalytic conversion of a make-up gas (126, 226) comprising hydrogen and nitrogen in an ammonia synthesis loop, wherein at least a portion (18b, 18d, 21) of said second tail gas is a nitrogen source for said make-up gas (126, 226), and wherein the first tail gas provided by said step b) is entirely or substantially entirely subjected to said NO x -removal step c) and the resulting NO x -depleted tail gas splits into two portions, a first portion being used as nitrogen source to obtain said ammonia make-up gas and a second portion being work-expanded to produce power, or wherein the first tail gas provided by said step b) splits into two portions, a first portion being subjected to said removal step c) and a second portion being subjected to a further step for removal of NO x, thus providing two streams having a lower content of nitrogen oxides than said first tail gas, a first stream being a nitrogen source for said ammonia make-up gas and a second stream being work-expanded to produce power.