The ratification process for Sweden and Finland as new NATO members officially begins Tuesday, Alliance Secretary General Jens Stoltenberg said during the open part of the signing ceremony for the respective protocols.

"Today we will officially sign the accession protocols. This marks the beginning of ratification," Stoltenberg said.

Finland and Sweden completed accession talks at NATO headquarters in Brussels on July 4, as agreed last week by NATO leaders at the Madrid summit. The two countries formally confirmed their willingness and ability to fulfill their political, legal and military obligations and commitments to NATO membership.

The talks were held between NATO officials and representatives from Finland and Sweden. The Finnish delegation was led by Foreign Minister Pekka Haavisto and Defense Minister Antti Kaikkonen, the Swedish delegation by Foreign Minister Ann Linde. The meetings for each country were chaired by NATO Assistant Secretary General for Political Affairs and Security Policy Ambassador Bettin Kadenbach.

At the conclusion of the talks, the allies were expected to sign protocols for Finland and Sweden to join NATO headquarters on Tuesday, July 5.

"At NATO headquarters in Brussels, the accession protocols necessary for the admission of Sweden and Finland were signed. Representatives from all 30 member states attended the ceremony," Spiegel writes.

The accession protocols will then be sent for ratification to all NATO countries according to their national procedures.