The Vatican body, the Congregation for the Doctrine of the Faith, has sent a letter reportedly with the approval of Pope Francis to German bishops rejecting their proposal to allow some Protestant spouses to receive communion, various Catholic news outlets reported.

The story was originally revealed yesterday by the Austrian website Kath.net and, according to the National Catholic Reporter (NCR), the pope does not wish the letter to be made public.

Sources have told the outlets that Archbishop Luis Ladaria, the current prefect of the CDF, wrote the letter and that it was given papal approval.

'It's a rejection of the pastoral plan,' an anonymous German Church source told NCR, adding that there are 'no differences' between Archbishop Ladaria and his predecessor, Cardinal Gerhard Müller, on the issue.

The Vatican response came after seven German bishops, led by Cardinal Rainer Woelki of Cologne, wrote to the CDF last month to say they believed the proposal to allow some Protestant spouses to receive communion contradicted Catholic doctrine, undermined Church unity and exceeded the competence of the bishops' conference.

This came after Germany's bishops voted overwhelmingly in favour at their spring conference in February of producing a guide, or pastoral handout, to allow a Protestant partner of a Catholic to receive the Eucharist in some cases and under certain conditions.

The bishops concluded that permission could be granted if, having made a 'serious examination' of conscience with a priest or another person with pastoral responsibilities, the spouse 'affirms the faith of the Catholic Church', wishes to end 'serious spiritual distress' and has a 'longing to satisfy a hunger for the Eucharist'.

Cardinal Reinhard Marx, the president of the German bishops' conference, said that the guide would be a 'pastoral handout' and that the intention was not to 'change any doctrine'.

But Cardinal Müller called the proposal a 'rhetorical trick,' stressing that interdenominational marriage is 'not an emergency situation,' and that 'neither the pope nor we bishops can redefine the sacraments as a means of alleviating mental distress and satisfying spiritual needs' as they are 'effective signs of the grace of God'.

According to the NCR, news of the Vatican's decision will come as an embarrassment to Cardinal Marx who is facing a revolt by bishops in Bavaria. The German daily newspaper Bild noted this week that 'five out of six Bavarian bishops have publicly challenged Marx on a central question [Communion],' and that his 'power base is damaged'.

The NCR speculated that the pope may want the letter to remain secret because it does not chime with the general, open direction of his pontificate.

In an interview with Christian Today, the pope's spokesman, Greg Burke, last month stressed that Francis's message of love was for all people, not just Catholics.