The European Union urged the governor of Texas on Tuesday to halt all executions before the U.S. state carries out its 400th death sentence since reinstatement of the penalty in 1976.

"The European Union notes with great regret the upcoming execution in the State of Texas," the Portuguese presidency of the 27-nation bloc said in a statement.

Texas is expected to hit the 400 mark on Wednesday -- putting it far ahead of any other U.S. state -- with the execution of Johnny Ray Conner for the 1998 shooting of a grocery store clerk.

"The European Union strongly urges Governor Rick Perry to exercise all powers vested in his office to halt all upcoming executions and to consider the introduction of a moratorium in the State of Texas," the EU statement said.

The European Union, which on Tuesday called the death penalty "cruel and inhumane", is opposed to all capital punishment and has called for its worldwide abolition.

"There is no evidence to suggest that the use of the death penalty serves as a deterrent against violent crime," the statement said, adding that its irreversibility meant that miscarriages of justice could not be redressed.

The U.S. Supreme Court lifted a ban on capital punishment in 1976. Around 1,090 executions have taken place in the United States in what some refer to as the 'modern' capital punishment era which began in Utah in January 1977, with the firing squad execution of Gary Gilmore.