var uploadedParts []CompletePart
	res, err := api.NewMultipartUpload(context.Background(), tgtBucket, tgtObject, opts)
	if err != nil {
		return err
	}

	defer func() {
		if err != nil {
			// block and abort remote upload upon failure.
			attempts := 1
			for attempts <= 3 {
				aerr := api.AbortMultipartUpload(ctx, tgtBucket, tgtObject, res.UploadID, ObjectOptions{})
				if aerr == nil {
					return
				}