There will be at least two credible challengers to Sepp Blatter’s Fifa presidency when nominations close at the end of this week, after the Dutch Football Association president, Michael van Praag, announced his intention to stand.

Van Praag was one of the Uefa delegates who launched an outspoken attack on Blatter’s regime before the World Cup in Brazil, calling on the 78-year-old to stand down at the end of his current term as he had previously promised to do.

The Uefa executive committee member and former Ajax president said he had hoped for another European candidate to come forward but that he had decided to step up. It is understood he has received pledges for the requisite five nominations from Fifa’s 209 member associations.

“It is well-known that I am very worried about Fifa,” Van Praag said. “It is high time that the organisation comes back into the real world. I had hoped that a credible opponent [to Blatter] would emerge but that’s simply not happened. In that case you cannot just talk but you must also act decisively and take responsibility, so there therefore I am announcing my candidacy.”

The Dutch FA secretary general, Bert van Oostveen, said: “It is clear that something has to change in Fifa to restore credibility. Michael is the right man for this. The KNVB will fully support him in his campaign.”

Van Praag’s announcement came hours after Blatter had called on Uefa to be “respectful” towards his campaign to stand for a fifth term, insisting his “mission” in football was not yet finished.

“All those who want to get rid of me should come,” he told CNN. “All this opposition is coming now, it’s unfortunate to say, but it’s true, it’s coming from Nyon, from Uefa. They don’t have the courage to come in. So let me go [on] – be respectful.”

Van Praag’s criticism of Blatter in São Paulo last year followed a stormy Uefa meeting that preceded the Fifa congress. Afterwards, Blatter said he had never been so offended. “The image of Fifa has been tarnished by everything that has happened over the last years,” Van Praag said at the time. “There are very few people who still take Fifa seriously and whatever way you want to cut and dice it, Blatter is responsible in the end.”

Prince Ali of Jordan, who is a Fifa vice-president but could lose his place on the executive committee as a result of Asian Football Confederation reforms, has announced his intention to stand. Uefa’s president, Michel Platini, has voiced his support for Ali’s decision but is also likely to welcome Van Praag’s announcement in the belief that the more credible challengers that emerge to Blatter the better. Platini announced last year that he had decided against standing in order to concentrate on his Uefa role.

Jérôme Champagne, a former Blatter ally who has been preparing the ground for his candidacy for more than a year, said last week he was making progress in gaining the five requisite nominations but had yet to make it over the line. The former France international David Ginola also plans to stand as part of a publicity stunt backed by a well-known bookmaker.

Ali and Van Praag will face an uphill struggle to unseat Blatter at Fifa’s congress in May but their supporters are taking heart from the fact their presence in the campaign will make life uncomfortable for the Swiss.

Van Praag said his background made him an ideal candidate to reform Fifa. “The Fifa has to be normalised and the Fifa has to be modernised,” he said. “And in my business life, but also in Ajax and also in my [Dutch] association, I went through this exercise many, many times, so I have a lot of experience in that aspect. So I believe I am the right person to do it.”

Although all those who wish to stand must make their intentions known by Thursday by writing to Fifa containing evidence of their nominations and proof of their active involvement in football for two of the past five years, there is not expected to be any confirmation of those candidates standing until next week at the earliest.

In 2011 Blatter was re-elected unopposed, despite an avalanche of corruption allegations in the wake of the contentious race for the 2018 and 2022 World Cups. His only rival, the Qatari Mohamed Bin Hammam, was forced to withdraw in the face of bribery allegations that subsequently led to him being banned for life.